diff --git a/Library/Homebrew/dev-cmd/test-bot.rb b/Library/Homebrew/dev-cmd/test-bot.rb
index e3ba7e41ef..94775e98d8 100644
--- a/Library/Homebrew/dev-cmd/test-bot.rb
+++ b/Library/Homebrew/dev-cmd/test-bot.rb
@@ -920,6 +920,7 @@ module Homebrew
     end
 
     ENV["HOMEBREW_DEVELOPER"] = "1"
+    ENV["HOMEBREW_NO_AUTO_UPDATE"] = "1"
     ENV["HOMEBREW_SANDBOX"] = "1"
     ENV["HOMEBREW_RUBY_MACHO"] = "1" if RUBY_TWO
     ENV["HOMEBREW_NO_EMOJI"] = "1"