diff --git a/doc/source/command-objects/image.rst b/doc/source/command-objects/image.rst
index 842eab8d8a..5184f44698 100644
--- a/doc/source/command-objects/image.rst
+++ b/doc/source/command-objects/image.rst
@@ -78,7 +78,8 @@ Create/upload an image
 
 .. option:: --disk-format <disk-format>
 
-    Image disk format (default: raw)
+    Image disk format. The supported options are: ami, ari, aki, vhd, vmdk,
+    raw, qcow2, vhdx, vdi, and iso. The default format is: raw
 
 .. option:: --size <size>
 
@@ -337,7 +338,8 @@ Set image properties
 
 .. option:: --disk-format <disk-format>
 
-    Image disk format (default: raw)
+    Image disk format. The supported options are: ami, ari, aki, vhd, vmdk,
+    raw, qcow2, vhdx, vdi, and iso.
 
 .. option:: --size <size>
 
diff --git a/openstackclient/image/v1/image.py b/openstackclient/image/v1/image.py
index cf389d17b7..0d54e339e1 100644
--- a/openstackclient/image/v1/image.py
+++ b/openstackclient/image/v1/image.py
@@ -38,6 +38,8 @@ from openstackclient.i18n import _
 
 DEFAULT_CONTAINER_FORMAT = 'bare'
 DEFAULT_DISK_FORMAT = 'raw'
+DISK_CHOICES = ["ami", "ari", "aki", "vhd", "vmdk", "raw", "qcow2", "vhdx",
+                "vdi", "iso"]
 
 
 LOG = logging.getLogger(__name__)
@@ -89,8 +91,9 @@ class CreateImage(command.ShowOne):
             "--disk-format",
             default=DEFAULT_DISK_FORMAT,
             metavar="<disk-format>",
-            help=_("Image disk format "
-                   "(default: %s)") % DEFAULT_DISK_FORMAT,
+            choices=DISK_CHOICES,
+            help=_("Image disk format. The supported options are: %s. "
+                   "The default format is: raw") % ', '.join(DISK_CHOICES)
         )
         parser.add_argument(
             "--size",
@@ -502,14 +505,12 @@ class SetImage(command.Command):
             container_choices,
             choices=container_choices
         )
-        disk_choices = ["ami", "ari", "aki", "vhd", "vmdk", "raw", "qcow2",
-                        "vhdx", "vdi", "iso"]
         parser.add_argument(
             "--disk-format",
             metavar="<disk-format>",
-            help=_("Disk format of image. Acceptable formats: %s") %
-            disk_choices,
-            choices=disk_choices
+            choices=DISK_CHOICES,
+            help=_("Image disk format. The supported options are: %s.") %
+            ', '.join(DISK_CHOICES)
         )
         parser.add_argument(
             "--size",
diff --git a/openstackclient/image/v2/image.py b/openstackclient/image/v2/image.py
index 657277c0dc..4031952bc4 100644
--- a/openstackclient/image/v2/image.py
+++ b/openstackclient/image/v2/image.py
@@ -32,6 +32,8 @@ from openstackclient.identity import common
 
 DEFAULT_CONTAINER_FORMAT = 'bare'
 DEFAULT_DISK_FORMAT = 'raw'
+DISK_CHOICES = ["ami", "ari", "aki", "vhd", "vmdk", "raw", "qcow2", "vhdx",
+                "vdi", "iso"]
 
 
 LOG = logging.getLogger(__name__)
@@ -140,9 +142,10 @@ class CreateImage(command.ShowOne):
         parser.add_argument(
             "--disk-format",
             default=DEFAULT_DISK_FORMAT,
+            choices=DISK_CHOICES,
             metavar="<disk-format>",
-            help=_("Image disk format "
-                   "(default: %s)") % DEFAULT_DISK_FORMAT,
+            help=_("Image disk format. The supported options are: %s. "
+                   "The default format is: raw") % ', '.join(DISK_CHOICES)
         )
         parser.add_argument(
             "--min-disk",
@@ -650,8 +653,9 @@ class SetImage(command.Command):
         parser.add_argument(
             "--disk-format",
             metavar="<disk-format>",
-            help=_("Image disk format "
-                   "(default: %s)") % DEFAULT_DISK_FORMAT,
+            choices=DISK_CHOICES,
+            help=_("Image disk format. The supported options are: %s") %
+            ', '.join(DISK_CHOICES)
         )
         protected_group = parser.add_mutually_exclusive_group()
         protected_group.add_argument(
diff --git a/openstackclient/tests/unit/image/v1/test_image.py b/openstackclient/tests/unit/image/v1/test_image.py
index aef74f0467..036c833651 100644
--- a/openstackclient/tests/unit/image/v1/test_image.py
+++ b/openstackclient/tests/unit/image/v1/test_image.py
@@ -116,7 +116,7 @@ class TestImageCreate(TestImage):
         self.images_mock.configure_mock(**mock_exception)
         arglist = [
             '--container-format', 'ovf',
-            '--disk-format', 'fs',
+            '--disk-format', 'ami',
             '--min-disk', '10',
             '--min-ram', '4',
             '--protected',
@@ -126,7 +126,7 @@ class TestImageCreate(TestImage):
         ]
         verifylist = [
             ('container_format', 'ovf'),
-            ('disk_format', 'fs'),
+            ('disk_format', 'ami'),
             ('min_disk', 10),
             ('min_ram', 4),
             ('protected', True),
@@ -147,7 +147,7 @@ class TestImageCreate(TestImage):
         self.images_mock.create.assert_called_with(
             name=self.new_image.name,
             container_format='ovf',
-            disk_format='fs',
+            disk_format='ami',
             min_disk=10,
             min_ram=4,
             protected=True,
diff --git a/openstackclient/tests/unit/image/v2/test_image.py b/openstackclient/tests/unit/image/v2/test_image.py
index ebc9c3a759..2f2212e4c3 100644
--- a/openstackclient/tests/unit/image/v2/test_image.py
+++ b/openstackclient/tests/unit/image/v2/test_image.py
@@ -130,7 +130,7 @@ class TestImageCreate(TestImage):
         self.images_mock.configure_mock(**mock_exception)
         arglist = [
             '--container-format', 'ovf',
-            '--disk-format', 'fs',
+            '--disk-format', 'ami',
             '--min-disk', '10',
             '--min-ram', '4',
             ('--protected'
@@ -143,7 +143,7 @@ class TestImageCreate(TestImage):
         ]
         verifylist = [
             ('container_format', 'ovf'),
-            ('disk_format', 'fs'),
+            ('disk_format', 'ami'),
             ('min_disk', 10),
             ('min_ram', 4),
             ('protected', self.new_image.protected),
@@ -165,7 +165,7 @@ class TestImageCreate(TestImage):
         self.images_mock.create.assert_called_with(
             name=self.new_image.name,
             container_format='ovf',
-            disk_format='fs',
+            disk_format='ami',
             min_disk=10,
             min_ram=4,
             owner=self.project.id,
@@ -193,7 +193,7 @@ class TestImageCreate(TestImage):
 
         arglist = [
             '--container-format', 'ovf',
-            '--disk-format', 'fs',
+            '--disk-format', 'ami',
             '--min-disk', '10',
             '--min-ram', '4',
             '--owner', 'unexist_owner',
@@ -203,7 +203,7 @@ class TestImageCreate(TestImage):
         ]
         verifylist = [
             ('container_format', 'ovf'),
-            ('disk_format', 'fs'),
+            ('disk_format', 'ami'),
             ('min_disk', 10),
             ('min_ram', 4),
             ('owner', 'unexist_owner'),
@@ -227,7 +227,7 @@ class TestImageCreate(TestImage):
 
         arglist = [
             '--container-format', 'ovf',
-            '--disk-format', 'fs',
+            '--disk-format', 'ami',
             '--min-disk', '10',
             '--min-ram', '4',
             '--protected',
@@ -237,7 +237,7 @@ class TestImageCreate(TestImage):
         ]
         verifylist = [
             ('container_format', 'ovf'),
-            ('disk_format', 'fs'),
+            ('disk_format', 'ami'),
             ('min_disk', 10),
             ('min_ram', 4),
             ('protected', True),