diff --git a/t/test-lib.sh b/t/test-lib.sh
index c081668dfe1..f7e55b1001f 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -91,6 +91,7 @@ unset VISUAL EMAIL LANGUAGE COLUMNS $("$PERL_PATH" -e '
 		VALGRIND
 		UNZIP
 		PERF_
+		CURL_VERBOSE
 	));
 	my @vars = grep(/^GIT_/ && !/^GIT_($ok)/o, @env);
 	print join("\n", @vars);