diff --git a/.github/workflows/node-test.yml b/.github/workflows/node-test.yml
index fcb46816eb9..f088faa2e79 100644
--- a/.github/workflows/node-test.yml
+++ b/.github/workflows/node-test.yml
@@ -84,7 +84,7 @@ jobs:
   #     - name: Setup Java JDK
   #       uses: actions/setup-java@v3.3.0
   #       with:
-  #         java-version: 17
+  #         java-version: 21
   #         distribution: temurin
 
   #     - uses: actions/checkout@v4
@@ -188,6 +188,11 @@ jobs:
           node-version: ${{ matrix.node-version }}
           cache: npm
           cache-dependency-path: npm-shrinkwrap.json
+      - name: Setup Java JDK
+        uses: actions/setup-java@v3.3.0
+        with:
+          java-version: 21
+          distribution: temurin
       - name: Setup Chrome
         uses: browser-actions/setup-chrome@v1.7.2
         with:
@@ -247,7 +252,7 @@ jobs:
       - name: Setup Java JDK
         uses: actions/setup-java@v3.3.0
         with:
-          java-version: 17
+          java-version: 21
           distribution: temurin
 
       - uses: actions/checkout@v4
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4ffa9bd0696..47d045bda89 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1 +1,2 @@
 - Add a confirmation in `firebase init dataconnect` before asking for app idea description. (#9282)
+- [BREAKING] Removes support for running emulators with Java versions prior to 21.
diff --git a/src/emulator/commandUtils.ts b/src/emulator/commandUtils.ts
index 43cd9a72b05..843ae373d5e 100644
--- a/src/emulator/commandUtils.ts
+++ b/src/emulator/commandUtils.ts
@@ -589,5 +589,5 @@ export async function checkJavaMajorVersion(): Promise<number> {
 
 export const MIN_SUPPORTED_JAVA_MAJOR_VERSION = 21;
 export const JAVA_DEPRECATION_WARNING =
-  "firebase-tools will drop support for Java version < 21 soon in firebase-tools@15. " +
+  "firebase-tools no longer supports Java version before 21. " +
   "Please install a JDK at version 21 or above to get a compatible runtime.";
diff --git a/src/emulator/controller.ts b/src/emulator/controller.ts
index 88004d71783..9a9dbbe895f 100755
--- a/src/emulator/controller.ts
+++ b/src/emulator/controller.ts
@@ -298,8 +298,7 @@ export async function startAll(
   const deprecationNotices: string[] = [];
   if (targets.some(requiresJava)) {
     if ((await commandUtils.checkJavaMajorVersion()) < MIN_SUPPORTED_JAVA_MAJOR_VERSION) {
-      utils.logLabeledError("emulators", JAVA_DEPRECATION_WARNING, "warn");
-      deprecationNotices.push(JAVA_DEPRECATION_WARNING);
+      throw new FirebaseError(JAVA_DEPRECATION_WARNING);
     }
   }
   if (options.logVerbosity) {