diff --git a/Library/Homebrew/dev-cmd/tests.rb b/Library/Homebrew/dev-cmd/tests.rb
index 9b15f9f3ef80e021217c13de3ff599c8b00eef1a..4e2d3b2db85c30a238f75ffb885a560e2d7d5810 100644
--- a/Library/Homebrew/dev-cmd/tests.rb
+++ b/Library/Homebrew/dev-cmd/tests.rb
@@ -7,6 +7,8 @@ require "tap"
 module Homebrew
   def tests
     (HOMEBREW_LIBRARY/"Homebrew").cd do
+      ENV.delete "HOMEBREW_VERBOSE"
+      ENV.delete "VERBOSE"
       ENV["HOMEBREW_NO_ANALYTICS_THIS_RUN"] = "1"
       ENV["HOMEBREW_DEVELOPER"] = "1"
       ENV["TESTOPTS"] = "-v" if ARGV.verbose?