diff --git a/hmp.c b/hmp.c
index 679467d85a..a25c7bd9a8 100644
--- a/hmp.c
+++ b/hmp.c
@@ -381,7 +381,7 @@ void hmp_info_cpus(Monitor *mon, const QDict *qdict)
 
         monitor_printf(mon, "%c CPU #%" PRId64 ":", active,
                        cpu->value->cpu_index);
-        monitor_printf(mon, " thread-id=%" PRId64 "\n", cpu->value->thread_id);
+        monitor_printf(mon, " thread_id=%" PRId64 "\n", cpu->value->thread_id);
     }
 
     qapi_free_CpuInfoFastList(cpu_list);