diff --git a/src/google/adk/cli/cli_create.py b/src/google/adk/cli/cli_create.py
index 3e5a5b0ed9..d860e9022a 100644
--- a/src/google/adk/cli/cli_create.py
+++ b/src/google/adk/cli/cli_create.py
@@ -72,28 +72,31 @@
 """
 
 
-def _ensure_dotenv_gitignored(agent_folder: str) -> None:
-  """Ensures generated secrets are excluded from version control."""
+def _ensure_generated_files_gitignored(agent_folder: str) -> None:
+  """Ensures generated secrets and runtime data are excluded from version control."""
   gitignore_file_path = os.path.join(agent_folder, ".gitignore")
-  dotenv_entry = ".env"
+  generated_entries = (".env", ".adk/")
 
   if not os.path.exists(gitignore_file_path):
     with open(gitignore_file_path, "w", encoding="utf-8") as f:
-      f.write(f"{dotenv_entry}\n")
+      f.write("\n".join(generated_entries) + "\n")
     return
 
   with open(gitignore_file_path, "r", encoding="utf-8") as f:
     content = f.read()
 
   existing_lines = content.splitlines()
-  if dotenv_entry in existing_lines:
+  missing_entries = tuple(
+      entry for entry in generated_entries if entry not in existing_lines
+  )
+  if not missing_entries:
     return
 
-  # Append .env, ensuring proper newline separation.
+  # Append generated entries, ensuring proper newline separation.
   with open(gitignore_file_path, "a", encoding="utf-8") as f:
     if content and not content.endswith("\n"):
       f.write("\n")
-    f.write(f"{dotenv_entry}\n")
+    f.write("\n".join(missing_entries) + "\n")
 
 
 def _generate_files(
@@ -126,7 +129,7 @@ def _generate_files(
     if google_cloud_region:
       lines.append(f"GOOGLE_CLOUD_LOCATION={google_cloud_region}")
     f.write("\n".join(lines))
-  _ensure_dotenv_gitignored(agent_folder)
+  _ensure_generated_files_gitignored(agent_folder)
 
   if type == "config":
     with open(agent_config_file_path, "w", encoding="utf-8") as f:
diff --git a/tests/unittests/cli/utils/test_cli_create.py b/tests/unittests/cli/utils/test_cli_create.py
index 98e0a92f88..6265342ece 100644
--- a/tests/unittests/cli/utils/test_cli_create.py
+++ b/tests/unittests/cli/utils/test_cli_create.py
@@ -69,7 +69,7 @@ def test_generate_files_with_api_key(agent_folder: Path) -> None:
   env_content = (agent_folder / ".env").read_text()
   assert "GOOGLE_API_KEY=dummy-key" in env_content
   assert "GOOGLE_GENAI_USE_ENTERPRISE=0" in env_content
-  assert (agent_folder / ".gitignore").read_text() == ".env\n"
+  assert (agent_folder / ".gitignore").read_text() == ".env\n.adk/\n"
   assert (agent_folder / "agent.py").exists()
   assert (agent_folder / "__init__.py").exists()
 
@@ -151,7 +151,7 @@ def test_generate_files_no_params(agent_folder: Path) -> None:
     assert key not in env_content
 
 
-def test_generate_files_appends_dotenv_to_existing_gitignore(
+def test_generate_files_appends_generated_entries_to_existing_gitignore(
     agent_folder: Path,
 ) -> None:
   """Existing .gitignore entries should be preserved."""
@@ -162,10 +162,12 @@ def test_generate_files_appends_dotenv_to_existing_gitignore(
       str(agent_folder), model="gemini-2.0-flash-001", type="code"
   )
 
-  assert (agent_folder / ".gitignore").read_text() == "__pycache__\n.env\n"
+  assert (
+      agent_folder / ".gitignore"
+  ).read_text() == "__pycache__\n.env\n.adk/\n"
 
 
-def test_generate_files_appends_dotenv_to_existing_gitignore_with_newline(
+def test_generate_files_appends_generated_entries_to_existing_gitignore_with_newline(
     agent_folder: Path,
 ) -> None:
   """Existing .gitignore entries ending in a newline should not cause extra blank lines."""
@@ -176,13 +178,31 @@ def test_generate_files_appends_dotenv_to_existing_gitignore_with_newline(
       str(agent_folder), model="gemini-2.0-flash-001", type="code"
   )
 
-  assert (agent_folder / ".gitignore").read_text() == "__pycache__\n.env\n"
+  assert (
+      agent_folder / ".gitignore"
+  ).read_text() == "__pycache__\n.env\n.adk/\n"
 
 
-def test_generate_files_does_not_duplicate_dotenv_gitignore_entry(
+def test_generate_files_does_not_duplicate_generated_gitignore_entries(
     agent_folder: Path,
 ) -> None:
-  """Existing .env ignore entries should not be duplicated."""
+  """Existing generated-file entries should not be duplicated."""
+  agent_folder.mkdir(parents=True, exist_ok=True)
+  (agent_folder / ".gitignore").write_text("__pycache__\n.env\n.adk/\n")
+
+  cli_create._generate_files(
+      str(agent_folder), model="gemini-2.0-flash-001", type="code"
+  )
+
+  assert (
+      agent_folder / ".gitignore"
+  ).read_text() == "__pycache__\n.env\n.adk/\n"
+
+
+def test_generate_files_adds_missing_runtime_entry(
+    agent_folder: Path,
+) -> None:
+  """Existing .env entries should not prevent adding the runtime directory."""
   agent_folder.mkdir(parents=True, exist_ok=True)
   (agent_folder / ".gitignore").write_text("__pycache__\n.env\n")
 
@@ -190,7 +210,9 @@ def test_generate_files_does_not_duplicate_dotenv_gitignore_entry(
       str(agent_folder), model="gemini-2.0-flash-001", type="code"
   )
 
-  assert (agent_folder / ".gitignore").read_text() == "__pycache__\n.env\n"
+  assert (
+      agent_folder / ".gitignore"
+  ).read_text() == "__pycache__\n.env\n.adk/\n"
 
 
 # run_cmd
@@ -274,7 +296,7 @@ def test_run_cmd_with_type_config(
   env_file = agent_dir / ".env"
   assert env_file.exists()
   assert "GOOGLE_API_KEY=test-key" in env_file.read_text()
-  assert (agent_dir / ".gitignore").read_text() == ".env\n"
+  assert (agent_dir / ".gitignore").read_text() == ".env\n.adk/\n"
 
 
 # Prompt helpers