diff --git a/injector.ts b/injector.ts
index cbc83a9..45b832a 100644
--- a/injector.ts
+++ b/injector.ts
@@ -53,6 +53,8 @@ export async function getDenoDir() {
         Deno.env.get("HOME") + "/.cache") + "/deno";
     case "darwin":
       return Deno.env.get("HOME") + "/Library/Caches/deno";
+    case "windows":
+      return Deno.env.get("LOCALAPPDATA") + "/deno";
   }
 }
 
diff --git a/injector_test.ts b/injector_test.ts
index f15a30a..cde5c9e 100644
--- a/injector_test.ts
+++ b/injector_test.ts
@@ -5,11 +5,12 @@ const os = Deno.build.os;
 
 Deno.env.delete("DENO_DIR");
 Deno.env.set("HOME", "testhome");
+Deno.env.set("LOCALAPPDATA", "testhome");
 Deno.env.delete("XDG_CACHE_HOME");
 
 Deno.test({
   name: "hoge",
-  ignore: os !== "linux" && os !== "darwin",
+  ignore: os !== "linux" && os !== "darwin" && os !== "windows",
   async fn() {
     if (os === "linux") {
       assertEquals(await getDenoDir(), "testhome/.cache/deno");
@@ -17,6 +18,8 @@ Deno.test({
       assertEquals(await getDenoDir(), "testcachehome/deno");
     } else if (os === "darwin") {
       assertEquals(await getDenoDir(), "testhome/Library/Caches/deno");
+    } else if (os === "windows") {
+      assertEquals(await getDenoDir(), "testhome/deno");
     }
     Deno.env.set("DENO_DIR", "testdenodir");
     assertEquals(await getDenoDir(), "testdenodir");