diff --git a/aquilon/netbox2aquilon.py b/aquilon/netbox2aquilon.py
index a2d30e0..5b97880 100755
--- a/aquilon/netbox2aquilon.py
+++ b/aquilon/netbox2aquilon.py
@@ -140,12 +140,15 @@ def _netbox_copy_vm_disks(self, virtual_machine):
         if virtual_disks:
             boot = True
             for disk in virtual_disks:
+                # Netbox stores virtual disk size in MB, Aquilon needs it in GB
+                # For netbox 1000 MB = 1GB
+                virtual_disk_gb = round(disk.size / 1000) # to nearest GB
                 cmd = [
                     'add_disk',
                     '--machine', f'{virtual_machine.aq_machine_name}',
                     '--disk', f'{disk.name}',
                     '--controller', 'sata',
-                    '--size', f'{disk.size}',
+                    '--size', f'{virtual_disk_gb}',
                 ]
                 if boot:
                     cmd.append('--boot')
@@ -154,12 +157,14 @@ def _netbox_copy_vm_disks(self, virtual_machine):
                     cmd += ['--comments', f'"{disk.description}"']
                 cmds.append(cmd)
         else:
+            # Netbox stores disk size in MB, Aquilon needs it in GB
+            disk_gb = round(virtual_machine.disk / 1000) # to nearest GB
             cmds.append([
                 'add_disk',
                 '--machine', f'{virtual_machine.aq_machine_name}',
                 '--disk', 'sda',
                 '--controller', 'sata',
-                '--size', f'{virtual_machine.disk}',
+                '--size', f'{disk_gb}',
                 '--boot',
             ])
 
diff --git a/aquilon/testdata/disks_virtual.json b/aquilon/testdata/disks_virtual.json
index 90dc111..a2b5809 100644
--- a/aquilon/testdata/disks_virtual.json
+++ b/aquilon/testdata/disks_virtual.json
@@ -11,7 +11,7 @@
     },
     "name": "sda",
     "description": "",
-    "size": 40,
+    "size": 40000,
     "tags": [],
     "custom_fields": {},
     "created": "2025-06-02T13:43:40.552134Z",
@@ -29,7 +29,7 @@
     },
     "name": "sdb",
     "description": "",
-    "size": 100,
+    "size": 100000,
     "tags": [],
     "custom_fields": {},
     "created": "2025-06-02T13:43:49.494852Z",
@@ -47,7 +47,7 @@
     },
     "name": "sdc",
     "description": "/opt",
-    "size": 100,
+    "size": 100000,
     "tags": [],
     "custom_fields": {},
     "created": "2025-06-02T13:44:01.016349Z",