diff --git a/src/libraries/System.Net.Security/tests/StressTests/SslStress/run-docker-compose.sh b/src/libraries/System.Net.Security/tests/StressTests/SslStress/run-docker-compose.sh
index ee1ec60f6c0a0..d8b096ec86c18 100755
--- a/src/libraries/System.Net.Security/tests/StressTests/SslStress/run-docker-compose.sh
+++ b/src/libraries/System.Net.Security/tests/StressTests/SslStress/run-docker-compose.sh
@@ -71,7 +71,7 @@ if [[ "$buildcurrentlibraries" -eq 1 ]]; then
 fi
 
 build_args=""
-if [[ -z "$imagename" ]]; then
+if [[ -n "$imagename" ]]; then
     build_args=" --build-arg SDK_BASE_IMAGE=$imagename"
 fi