diff --git a/nova/api/openstack/placement/handlers/allocation.py b/nova/api/openstack/placement/handlers/allocation.py
index b8b8e7aead26..435ff54dec44 100644
--- a/nova/api/openstack/placement/handlers/allocation.py
+++ b/nova/api/openstack/placement/handlers/allocation.py
@@ -51,7 +51,8 @@ ALLOCATION_SCHEMA = {
                         "type": "object",
                         "patternProperties": {
                             "^[0-9A-Z_]+$": {
-                                "type": "integer"
+                                "type": "integer",
+                                "minimum": 1,
                             }
                         },
                         "additionalProperties": False
diff --git a/nova/tests/functional/api/openstack/placement/gabbits/allocations.yaml b/nova/tests/functional/api/openstack/placement/gabbits/allocations.yaml
index 61c060805774..0aaa9b06e2c6 100644
--- a/nova/tests/functional/api/openstack/placement/gabbits/allocations.yaml
+++ b/nova/tests/functional/api/openstack/placement/gabbits/allocations.yaml
@@ -93,6 +93,34 @@ tests:
       max_unit: 1024
   status: 201
 
+- name: put an allocation with zero usage
+  PUT: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
+  request_headers:
+      content-type: application/json
+  data:
+      allocations:
+          - resource_provider:
+                uuid: $ENVIRON['RP_UUID']
+            resources:
+                DISK_GB: 0
+  status: 400
+  response_strings:
+      - "JSON does not validate: 0 is less than the minimum of 1"
+      - Failed validating 'minimum' in schema
+
+- name: put an allocation with omitted usage
+  PUT: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
+  request_headers:
+      content-type: application/json
+  data:
+      allocations:
+          - resource_provider:
+                uuid: $ENVIRON['RP_UUID']
+  status: 400
+  response_strings:
+      - Failed validating 'required' in schema
+
+
 - name: put an allocation
   PUT: /allocations/599ffd2d-526a-4b2e-8683-f13ad25f9958
   request_headers: