diff --git a/test/gemm-microkernel-tester.cc b/test/gemm-microkernel-tester.cc
index 2f2aebe6409..0e31a581f5a 100644
--- a/test/gemm-microkernel-tester.cc
+++ b/test/gemm-microkernel-tester.cc
@@ -69,7 +69,7 @@ TEST_P(GemmTest, Test) {
             if (params.loop_bzp_.is_set) {
               tester.b_zero_point(bzp);
             }
-            for (size_t bl = params.loop_bl_.from; bl <= tester.k() / 2;
+            for (size_t bl = params.loop_bl_.from; bl <= tester.k() == 1 ? 1 : tester.k() / 2;
                bl = params.loop_bl_.next(bl)) {
                if (params.loop_bl_.is_set) {
                 // Require block size to divide (padded) column size.