diff --git a/qapi-schema.json b/qapi-schema.json
index 14b498b442..dc2abe479e 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -2855,12 +2855,15 @@
 #
 # @help: #optional human readable text string, not suitable for parsing.
 #
+# @default: #optional default value string (since 2.1)
+#
 # Since 1.5
 ##
 { 'type': 'CommandLineParameterInfo',
   'data': { 'name': 'str',
             'type': 'CommandLineParameterType',
-            '*help': 'str' } }
+            '*help': 'str',
+            '*default': 'str' } }
 
 ##
 # @CommandLineOptionInfo:
diff --git a/qmp-commands.hx b/qmp-commands.hx
index d8aa4edabe..d6bb0f483f 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -2898,6 +2898,8 @@ Each array entry contains the following:
               or 'size')
     - "help": human readable description of the parameter
               (json-string, optional)
+    - "default": default value string for the parameter
+                 (json-string, optional)
 
 Example:
 
diff --git a/util/qemu-config.c b/util/qemu-config.c
index f4e4f38749..ba375c0148 100644
--- a/util/qemu-config.c
+++ b/util/qemu-config.c
@@ -82,6 +82,10 @@ static CommandLineParameterInfoList *query_option_descs(const QemuOptDesc *desc)
             info->has_help = true;
             info->help = g_strdup(desc[i].help);
         }
+        if (desc[i].def_value_str) {
+            info->has_q_default = true;
+            info->q_default = g_strdup(desc[i].def_value_str);
+        }
 
         entry = g_malloc0(sizeof(*entry));
         entry->value = info;