diff --git a/tests/unittests/tests-core/tests-core-atomic.c b/tests/unittests/tests-core/tests-core-atomic.c
index 867ab9b5d0cc77ff77586f8f1d54f7220ed21ba7..7089f9edfae83b21fdef6af8dcb3fa2654842f92 100644
--- a/tests/unittests/tests-core/tests-core-atomic.c
+++ b/tests/unittests/tests-core/tests-core-atomic.c
@@ -88,7 +88,7 @@ static void test_atomic_dec_positive(void)
 {
     atomic_int res = ATOMIC_VAR_INIT(99);
 
-    for (int i = 99; i < -123; --i) {
+    for (int i = 99; i > -123; --i) {
         TEST_ASSERT_EQUAL_INT(i, atomic_fetch_sub(&res, 1));
         TEST_ASSERT_EQUAL_INT(i - 1, atomic_load(&res));
     }