diff --git a/python/mozboot/mozboot/android.py b/python/mozboot/mozboot/android.py
index c19dd40d8501..19d145796de6 100644
--- a/python/mozboot/mozboot/android.py
+++ b/python/mozboot/mozboot/android.py
@@ -280,7 +280,7 @@ def ensure_android_packages(sdkmanager_tool, packages=None, no_interactive=False
 
     # Emulate yes.  For a discussion of passing input to check_output,
     # see https://stackoverflow.com/q/10103551.
-    yes = '\n'.join(['y']*100)
+    yes = '\n'.join(['y']*100).encode("UTF-8")
     proc = subprocess.Popen(args,
                             stdout=subprocess.PIPE,
                             stderr=subprocess.STDOUT,