diff --git a/src/lib/utils/contest.ts b/src/lib/utils/contest.ts
index e22a5e76c..b4e701361 100644
--- a/src/lib/utils/contest.ts
+++ b/src/lib/utils/contest.ts
@@ -459,12 +459,19 @@ export function getJoiContestLabel(contestId: string): string {
 
       let newLabel = base.toUpperCase();
       newLabel += addJoiSubTypeIfNeeds(subType);
-      newLabel += SPACE;
-      newLabel += addJoiDivisionNameIfNeeds(division, qual);
+
+      if (division !== undefined) {
+        newLabel += SPACE;
+        newLabel += addJoiDivisionNameIfNeeds(division, qual);
+      }
+
       newLabel += SPACE;
       newLabel += addJoiYear(yearSuffix, yearPrefix);
-      newLabel += SPACE;
-      newLabel += addJoiQualRoundNameIfNeeds(qualRound);
+
+      if (qualRound !== undefined) {
+        newLabel += SPACE;
+        newLabel += addJoiQualRoundNameIfNeeds(qualRound);
+      }
 
       return newLabel;
     },
@@ -485,7 +492,9 @@ function addJoiSubTypeIfNeeds(subType: string): string {
 
 function addJoiDivisionNameIfNeeds(division: string, qual: string): string {
   if (division === 'yo') {
-    if (qual === '1') {
+    if (qual === undefined) {
+      return '予選';
+    } else if (qual === '1') {
       return '一次予選';
     } else if (qual === '2') {
       return '二次予選';
diff --git a/src/test/lib/utils/contest.test.ts b/src/test/lib/utils/contest.test.ts
index 9657bd9e4..d14c19f13 100644
--- a/src/test/lib/utils/contest.test.ts
+++ b/src/test/lib/utils/contest.test.ts
@@ -374,18 +374,6 @@ describe('Contest', () => {
         });
       });
 
-      // TODO(#issue): Skipped until notational inconsistencies are resolved.
-      // Current issues:
-      // 1. Contest names use inconsistent formats
-      // 2. Need to standardize naming conventions across all contests
-      describe.skip('when contest_id contains joi', () => {
-        TestCasesForContestNameLabel.joi.forEach(({ name, value }) => {
-          runTests(`${name}`, [value], ({ contestId, expected }: TestCaseForContestNameLabel) => {
-            expect(getContestNameLabel(contestId)).toEqual(expected);
-          });
-        });
-      });
-
       describe('when contest_id contains chokudai_S', () => {
         TestCasesForContestNameLabel.atCoderOthers.forEach(({ name, value }) => {
           runTests(`${name}`, [value], ({ contestId, expected }: TestCaseForContestNameLabel) => {
@@ -446,6 +434,18 @@ describe('Contest', () => {
         });
       });
 
+      describe('when contest_id contains joi', () => {
+        TestCasesForContestNameAndTaskIndex.joi.forEach(({ name, value }) => {
+          runTests(
+            `${name}`,
+            [value],
+            ({ contestId, taskTableIndex, expected }: TestCaseForContestNameAndTaskIndex) => {
+              expect(addContestNameToTaskIndex(contestId, taskTableIndex)).toEqual(expected);
+            },
+          );
+        });
+      });
+
       describe('when contest_id is tessoku-book', () => {
         TestCasesForContestNameAndTaskIndex.tessokuBook.forEach(({ name, value }) => {
           runTests(
diff --git a/src/test/lib/utils/test_cases/contest_name_and_task_index.ts b/src/test/lib/utils/test_cases/contest_name_and_task_index.ts
index 40af31246..003962d45 100644
--- a/src/test/lib/utils/test_cases/contest_name_and_task_index.ts
+++ b/src/test/lib/utils/test_cases/contest_name_and_task_index.ts
@@ -1,6 +1,7 @@
 import { createTestCase, zip } from '../../common/test_helpers';
 import {
   getPastContestLabel,
+  getJoiContestLabel,
   getAtCoderUniversityContestLabel,
   getAojContestLabel,
   PAST_TRANSLATIONS,
@@ -147,6 +148,159 @@ export const past = Object.entries(PAST_TEST_DATA).flatMap(([contestId, tasks])
   generatePastTestCases(Array(tasks.tasks.length).fill(contestId), tasks.tasks),
 );
 
+const generateJoiTestCases = (
+  contestIds: string[],
+  taskIndices: string[],
+): { name: string; value: TestCaseForContestNameAndTaskIndex }[] => {
+  return zip(contestIds, taskIndices).map(([contestId, taskIndex]) => {
+    const testCase = createTestCaseForContestNameAndTaskIndex(`JOI, ${contestId} ${taskIndex}`)({
+      contestId: `${contestId}`,
+      taskTableIndex: `${taskIndex}`,
+      expected: `${getJoiContestLabel(contestId)} - ${taskIndex}`,
+    });
+
+    return testCase;
+  });
+};
+
+const JOI_TEST_DATA = {
+  joi2006yo: {
+    contestId: 'joi2006yo',
+    tasks: ['A', 'B', 'C', 'D', 'E'],
+  },
+  joi2007yo: {
+    contestId: 'joi2007yo',
+    tasks: ['A', 'B', 'E', 'F'],
+  },
+  joi2018yo: {
+    contestId: 'joi2018yo',
+    tasks: ['A', 'B', 'F'],
+  },
+  joi2024yo1c: {
+    contestId: 'joi2024yo1c',
+    tasks: ['A', 'B', 'C', 'D'],
+  },
+  joi2025yo1a: {
+    contestId: 'joi2025yo1a',
+    tasks: ['A', 'B', 'D'],
+  },
+  joi2025yo1b: {
+    contestId: 'joi2025yo1b',
+    tasks: ['A', 'B', 'D'],
+  },
+  joi2023yo2: {
+    contestId: 'joi2023yo2',
+    tasks: ['A', 'B', 'C', 'D', 'E'],
+  },
+  joi2024yo2: {
+    contestId: 'joi2024yo2',
+    tasks: ['A', 'B', 'E'],
+  },
+  joi2006ho: {
+    contestId: 'joi2006ho',
+    tasks: ['A', 'B', 'C', 'D', 'E'],
+  },
+  joi2007ho: {
+    contestId: 'joi2007ho',
+    tasks: ['A', 'B', 'E'],
+  },
+  joi2023ho: {
+    contestId: 'joi2023ho',
+    tasks: ['A', 'B', 'E'],
+  },
+  joi2024ho: {
+    contestId: 'joi2024ho',
+    tasks: ['A', 'B', 'E'],
+  },
+  joisc2007: {
+    contestId: 'joisc2007',
+    tasks: ['anagra', 'buildi', 'salt', 'score'],
+  },
+  joisc2008: {
+    contestId: 'joisc2008',
+    tasks: ['belt', 'typhoon'],
+  },
+  joisc2022: {
+    contestId: 'joisc2022',
+    tasks: ['A', 'B', 'K', 'L'],
+  },
+  joisp2023: {
+    contestId: 'joisp2023',
+    tasks: ['A', 'B', 'K', 'L'],
+  },
+  joisp2024: {
+    contestId: 'joisp2024',
+    tasks: ['A', 'B', 'K', 'L'],
+  },
+  joiopen2024: {
+    contestId: 'joiopen2024',
+    tasks: ['A', 'B', 'C'],
+  },
+  'joig2021-open': {
+    contestId: 'joig2021-open',
+    tasks: ['A', 'B', 'C', 'D', 'E', 'F'],
+  },
+  'joig2022-open': {
+    contestId: 'joig2022-open',
+    tasks: ['A', 'B', 'F'],
+  },
+  'joig2023-open': {
+    contestId: 'joig2023-open',
+    tasks: ['A', 'B', 'F'],
+  },
+  joigsc2022: {
+    contestId: 'joigsc2022',
+    tasks: ['A', 'B', 'H'],
+  },
+  joigsp2023: {
+    contestId: 'joigsp2023',
+    tasks: ['A', 'B', 'H'],
+  },
+  joigsp2024: {
+    contestId: 'joigsp2024',
+    tasks: ['A', 'B', 'H'],
+  },
+};
+
+export const joi = Object.entries(JOI_TEST_DATA).flatMap(([contestId, tasks]) =>
+  generateJoiTestCases(Array(tasks.tasks.length).fill(contestId), tasks.tasks),
+);
+
+// export const joi = [
+//   createTestCaseForContestNameLabel('JOI 2018 qual')({
+//     contestId: 'joi2018yo',
+//     expected: '',
+//   }),
+//   createTestCaseForContestNameLabel('JOI 2024 qual 1A')({
+//     contestId: 'joi2024yo1a',
+//     expected: '',
+//   }),
+//   createTestCaseForContestNameLabel('JOI 2024 qual 1B')({
+//     contestId: 'joi2024yo1b',
+//     expected: '',
+//   }),
+//   createTestCaseForContestNameLabel('JOI 2024 qual 1C')({
+//     contestId: 'joi2024yo1c',
+//     expected: '',
+//   }),
+//   createTestCaseForContestNameLabel('JOIG 2021 open')({
+//     contestId: 'joig2021-open',
+//     expected: '',
+//   }),
+//   createTestCaseForContestNameLabel('JOIG 2022 open')({
+//     contestId: 'joig2022-open',
+//     expected: '',
+//   }),
+//   createTestCaseForContestNameLabel('JOIG 2023 open')({
+//     contestId: 'joig2023-open',
+//     expected: '',
+//   }),
+//   createTestCaseForContestNameLabel('JOIG 2024 open')({
+//     contestId: 'joig2024-open',
+//     expected: '',
+//   }),
+// ];
+
 export const tessokuBook = [
   createTestCaseForContestNameAndTaskIndex('Tessoku Book, Task A01')({
     contestId: 'tessoku-book',
diff --git a/src/test/lib/utils/test_cases/contest_name_labels.ts b/src/test/lib/utils/test_cases/contest_name_labels.ts
index ba03db349..9c7a8fa97 100644
--- a/src/test/lib/utils/test_cases/contest_name_labels.ts
+++ b/src/test/lib/utils/test_cases/contest_name_labels.ts
@@ -28,54 +28,6 @@ export const aclPractice = [
   }),
 ];
 
-// Note: Not yet implemented, because notational distortion needs to be corrected for each contest.
-export const joi = [
-  createTestCaseForContestNameLabel('JOIG 2024 open')({
-    contestId: 'joig2024-open',
-    expected: '',
-  }),
-  createTestCaseForContestNameLabel('JOIG 2023 open')({
-    contestId: 'joig2023-open',
-    expected: '',
-  }),
-  createTestCaseForContestNameLabel('JOIG 2022 open')({
-    contestId: 'joig2022-open',
-    expected: '',
-  }),
-  createTestCaseForContestNameLabel('JOIG 2021 open')({
-    contestId: 'joig2021-open',
-    expected: '',
-  }),
-  createTestCaseForContestNameLabel('JOI 2024 qual 1A')({
-    contestId: 'joi2024yo1a',
-    expected: '',
-  }),
-  createTestCaseForContestNameLabel('JOI 2024 qual 1B')({
-    contestId: 'joi2024yo1b',
-    expected: '',
-  }),
-  createTestCaseForContestNameLabel('JOI 2024 qual 1C')({
-    contestId: 'joi2024yo1c',
-    expected: '',
-  }),
-  createTestCaseForContestNameLabel('JOI 2023 qual 1A')({
-    contestId: 'joi2023yo1a',
-    expected: '',
-  }),
-  createTestCaseForContestNameLabel('JOI 2023 qual 1B')({
-    contestId: 'joi2023yo1b',
-    expected: '',
-  }),
-  createTestCaseForContestNameLabel('JOI 2023 qual 1C')({
-    contestId: 'joi2023yo1c',
-    expected: '',
-  }),
-  createTestCaseForContestNameLabel('JOI 2018 qual')({
-    contestId: 'joi2018yo',
-    expected: '',
-  }),
-];
-
 export const atCoderOthers = [
   createTestCaseForContestNameLabel('Chokudai SpeedRun 001')({
     contestId: 'chokudai_S001',
diff --git a/src/test/lib/utils/test_cases/contest_type.ts b/src/test/lib/utils/test_cases/contest_type.ts
index 2095c4516..352987ea0 100644
--- a/src/test/lib/utils/test_cases/contest_type.ts
+++ b/src/test/lib/utils/test_cases/contest_type.ts
@@ -88,17 +88,42 @@ export const aclPractice = [
 ];
 
 const joiContestData = [
-  { name: 'JOIG 2024 open', contestId: 'joig2024-open' },
-  { name: 'JOIG 2023 open', contestId: 'joig2023-open' },
-  { name: 'JOIG 2022 open', contestId: 'joig2022-open' },
-  { name: 'JOIG 2021 open', contestId: 'joig2021-open' },
+  { name: 'JOI 2006 qual', contestId: 'joi2006yo' },
+  { name: 'JOI 2007 qual', contestId: 'joi2007yo' },
+  { name: 'JOI 2018 qual', contestId: 'joi2018yo' },
+  { name: 'JOI 2019 qual', contestId: 'joi2019yo' },
   { name: 'JOI 2024 qual 1A', contestId: 'joi2024yo1a' },
   { name: 'JOI 2024 qual 1B', contestId: 'joi2024yo1b' },
   { name: 'JOI 2024 qual 1C', contestId: 'joi2024yo1c' },
-  { name: 'JOI 2023 qual 1A', contestId: 'joi2023yo1a' },
-  { name: 'JOI 2023 qual 1B', contestId: 'joi2023yo1b' },
-  { name: 'JOI 2023 qual 1C', contestId: 'joi2023yo1c' },
-  { name: 'JOI 2018 qual', contestId: 'joi2018yo' },
+  { name: 'JOI 2025 qual 1A', contestId: 'joi2025yo1a' },
+  { name: 'JOI 2025 qual 1B', contestId: 'joi2025yo1b' },
+  { name: 'JOI 2025 qual 1C', contestId: 'joi2025yo1c' },
+  { name: 'JOI 2020 qual 2', contestId: 'joi2020yo2' },
+  { name: 'JOI 2023 qual 2', contestId: 'joi2023yo2' },
+  { name: 'JOI 2024 qual 2', contestId: 'joi2024yo2' },
+  { name: 'JOI 2006 final', contestId: 'joi2006ho' },
+  { name: 'JOI 2007 final', contestId: 'joi2007ho' },
+  { name: 'JOI 2019 final', contestId: 'joi2019ho' },
+  { name: 'JOI 2020 final', contestId: 'joi2020ho' },
+  { name: 'JOI 2022 final', contestId: 'joi2022ho' },
+  { name: 'JOI 2023 final', contestId: 'joi2023ho' },
+  { name: 'JOI 2024 final', contestId: 'joi2024ho' },
+  { name: 'JOI 2007 Spring', contestId: 'joisc2007' },
+  { name: 'JOI 2008 Spring', contestId: 'joisc2008' },
+  { name: 'JOI 2020 Spring', contestId: 'joisc2020' },
+  { name: 'JOI 2022 Spring', contestId: 'joisc2022' },
+  { name: 'JOI 2023 Spring', contestId: 'joisp2023' },
+  { name: 'JOI 2024 Spring', contestId: 'joisp2024' },
+  { name: 'JOI Open 2022', contestId: 'joiopen2022' },
+  { name: 'JOI Open 2023', contestId: 'joiopen2023' },
+  { name: 'JOI Open 2024', contestId: 'joiopen2024' },
+  { name: 'JOIG 2021 open', contestId: 'joig2021-open' },
+  { name: 'JOIG 2022 open', contestId: 'joig2022-open' },
+  { name: 'JOIG 2023 open', contestId: 'joig2023-open' },
+  { name: 'JOIG 2024 open', contestId: 'joig2024-open' },
+  { name: 'JOIG 2022 Spring', contestId: 'joigsc2022' },
+  { name: 'JOIG 2023 Spring', contestId: 'joigsp2023' },
+  { name: 'JOIG 2024 Spring', contestId: 'joigsp2024' },
 ];
 
 export const joi = joiContestData.map(({ name, contestId }) =>