diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index a5ed8edeeff97bc21048b868783b16a55d079ae2..f674ba98b1a77c4e8aa1f34da2dae172b9767dfd 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3762,7 +3762,7 @@ qemuBuildDriveStr(virConnectPtr conn,
                           disk->blkdeviotune.write_iops_sec_max);
     }
 
-    if (disk->blkdeviotune.write_iops_sec_max) {
+    if (disk->blkdeviotune.size_iops_sec) {
         virBufferAsprintf(&opt, ",iops_size=%llu",
                           disk->blkdeviotune.size_iops_sec);
     }