diff --git a/releasenotes/notes/ironic-empty-log-config-57f81ea05b6c29d4.yaml b/releasenotes/notes/ironic-empty-log-config-57f81ea05b6c29d4.yaml
new file mode 100644
index 0000000000..3d991bfbd2
--- /dev/null
+++ b/releasenotes/notes/ironic-empty-log-config-57f81ea05b6c29d4.yaml
@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    Renders an empty ``log_config_append`` value when file-based Ironic
+    logging is disabled. This avoids serializing YAML ``null`` as the literal
+    ``<no value>`` filename in ``ironic.conf``.
diff --git a/roles/ironic/vars/main.yml b/roles/ironic/vars/main.yml
index 57a0f1b57e..9ce4bf980c 100644
--- a/roles/ironic/vars/main.yml
+++ b/roles/ironic/vars/main.yml
@@ -44,7 +44,7 @@ _ironic_helm_values:
   conf:
     ironic:
       DEFAULT:
-        log_config_append: null
+        log_config_append: ""
         enabled_network_interfaces: flat,neutron
         default_network_interface: flat
         rbac_service_role_elevated_access: true
diff --git a/roles/ironic/vars_test.go b/roles/ironic/vars_test.go
index f8bc0f96f0..4cc6aa57ad 100644
--- a/roles/ironic/vars_test.go
+++ b/roles/ironic/vars_test.go
@@ -61,3 +61,20 @@ func TestHelmValues(t *testing.T) {
 	testutils.TestAllPodsHaveRuntimeClass(t, vals)
 	testutils.TestAllPodsHavePriorityClass(t, vals)
 }
+func TestDisabledLogConfigRendersEmptyValue(t *testing.T) {
+	var values struct {
+		HelmValues struct {
+			Conf struct {
+				Ironic struct {
+					Default map[string]any `yaml:"DEFAULT"`
+				} `yaml:"ironic"`
+			} `yaml:"conf"`
+		} `yaml:"_ironic_helm_values"`
+	}
+	err := yaml.UnmarshalWithOptions(varsFile, &values)
+	require.NoError(t, err)
+	require.Contains(t, values.HelmValues.Conf.Ironic.Default,
+		"log_config_append")
+	require.Equal(t, "",
+		values.HelmValues.Conf.Ironic.Default["log_config_append"])
+}