diff --git a/ansible/provision-net.yml b/ansible/provision-net.yml
index 7476608eb44b52a050d00bcea19003669475e748..54a5b4fc6fbc4db45a4df84240eadede256592ea 100644
--- a/ansible/provision-net.yml
+++ b/ansible/provision-net.yml
@@ -18,6 +18,7 @@
     venv: "{{ virtualenv_path }}/openstacksdk"
     provision_net:
       name: "{{ kolla_ironic_provisioning_network }}"
+      mtu: "{{ provision_wl_net_name | net_mtu | default(omit, True) }}"
       provider_network_type: "{% if provision_wl_net_name | net_vlan %}vlan{% else %}flat{% endif %}"
       provider_physical_network: "{{ provision_wl_net_name | net_physical_network | default('physnet1', True) }}"
       provider_segmentation_id: "{{ provision_wl_net_name | net_vlan }}"
@@ -31,6 +32,7 @@
           allocation_pool_end: "{{ provision_wl_net_name | net_neutron_allocation_pool_end }}"
     cleaning_net:
       name: "{{ kolla_ironic_cleaning_network }}"
+      mtu: "{{ cleaning_net_name | net_mtu | default(omit, True) }}"
       provider_network_type: "{% if cleaning_net_name | net_vlan %}vlan{% else %}flat{% endif %}"
       provider_physical_network: "{{ cleaning_net_name | net_physical_network | default('physnet1', True) }}"
       provider_segmentation_id: "{{ cleaning_net_name | net_vlan }}"
diff --git a/releasenotes/notes/provision-net-mtu-befdda04224f49a6.yaml b/releasenotes/notes/provision-net-mtu-befdda04224f49a6.yaml
new file mode 100644
index 0000000000000000000000000000000000000000..ce736f5d2b939a4fef5f429a989174949340a182
--- /dev/null
+++ b/releasenotes/notes/provision-net-mtu-befdda04224f49a6.yaml
@@ -0,0 +1,5 @@
+---
+fixes:
+  - |
+    Fixes an issue where the MTU defined in Kayobe was not applied to Ironic
+    provisioning and cleaning networks in Neutron.