diff --git a/setup-ndk.sh b/setup-ndk.sh
index 637b0b4..2a3baaf 100644
--- a/setup-ndk.sh
+++ b/setup-ndk.sh
@@ -4,6 +4,11 @@ set -e
 export ANDROID_HOME="$HOME/Android/Sdk"
 export ANDROID_SDK_ROOT="$ANDROID_HOME"
 
+if [ -d "$ANDROID_HOME" ]; then
+  echo "Android SDK already exists at $ANDROID_HOME"
+  exit 0
+fi
+
 mkdir -p "$ANDROID_HOME/cmdline-tools"
 cd "$ANDROID_HOME"