diff --git a/src/net/http/proxy_test.go b/src/net/http/proxy_test.go
index 823d1447ee..8d3a78b962 100644
--- a/src/net/http/proxy_test.go
+++ b/src/net/http/proxy_test.go
@@ -75,7 +75,7 @@ func TestCacheKeys(t *testing.T) {
 
 func ResetProxyEnv() {
 	for _, v := range []string{"HTTP_PROXY", "http_proxy", "NO_PROXY", "no_proxy"} {
-		os.Setenv(v, "")
+		os.Unsetenv(v)
 	}
 	ResetCachedEnvironment()
 }
diff --git a/src/net/http/transport_test.go b/src/net/http/transport_test.go
index 09bfef4b10..8e211aad27 100644
--- a/src/net/http/transport_test.go
+++ b/src/net/http/transport_test.go
@@ -2243,6 +2243,7 @@ var proxyFromEnvTests = []proxyFromEnvTest{
 
 func TestProxyFromEnvironment(t *testing.T) {
 	ResetProxyEnv()
+	defer ResetProxyEnv()
 	for _, tt := range proxyFromEnvTests {
 		os.Setenv("HTTP_PROXY", tt.env)
 		os.Setenv("HTTPS_PROXY", tt.httpsenv)