diff --git a/releasenotes/notes/allow-updating-of-allowed-cidr-18d04641909ec3e3.yaml b/releasenotes/notes/allow-updating-of-allowed-cidr-18d04641909ec3e3.yaml
new file mode 100644
index 0000000..f005f0e
--- /dev/null
+++ b/releasenotes/notes/allow-updating-of-allowed-cidr-18d04641909ec3e3.yaml
@@ -0,0 +1,4 @@
+---
+features:
+  - |
+    Added ability to update allowed_cidr for an existing instance.
diff --git a/trove_dashboard/api/trove.py b/trove_dashboard/api/trove.py
index 3ff20af..5fddaeb 100644
--- a/trove_dashboard/api/trove.py
+++ b/trove_dashboard/api/trove.py
@@ -200,8 +200,8 @@ def instance_restart(request, instance_id):
     return troveclient(request).instances.restart(instance_id)
 
 
-def instance_update(request, instance_id, name=None):
-    return troveclient(request).instances.update(instance_id, name=name)
+def instance_update(request, instance_id, **kwargs):
+    return troveclient(request).instances.update(instance_id, **kwargs)
 
 
 def instance_detach_replica(request, instance_id):
diff --git a/trove_dashboard/content/databases/forms.py b/trove_dashboard/content/databases/forms.py
index 74690cb..be376d4 100644
--- a/trove_dashboard/content/databases/forms.py
+++ b/trove_dashboard/content/databases/forms.py
@@ -286,6 +286,16 @@ class AttachConfigurationForm(forms.SelfHandlingForm):
 class UpdateInstanceForm(forms.SelfHandlingForm):
     instance_id = forms.CharField(widget=forms.HiddenInput())
     instance_name = forms.CharField(label=_("Name"))
+    allowed_cidrs = forms.MultiIPField(
+        label=_("Allowed CIDRs"),
+        required=False,
+        help_text=_("Classless Inter-Domain Routing "
+                    "(e.g. 192.168.0.0/24, or "
+                    "2001:db8::/128). Can enter multiple values separating"
+                    "by a comma"),
+        version=forms.IPv4 | forms.IPv6,
+        mask=True,
+        widget=forms.TextInput())
 
     def __init__(self, request, *args, **kwargs):
         super(UpdateInstanceForm, self).__init__(request, *args, **kwargs)
@@ -294,9 +304,13 @@ class UpdateInstanceForm(forms.SelfHandlingForm):
 
     def handle(self, request, data):
         instance_id = data.get('instance_id')
+        allowed_cidrs = data.get('allowed_cidrs')
         instance_name = data.get('instance_name')
+        update_kwargs = {'name': instance_name}
+        if allowed_cidrs:
+            update_kwargs['allowed_cidrs'] = allowed_cidrs.split(',')
         try:
-            api.trove.instance_update(request, instance_id, instance_name)
+            api.trove.instance_update(request, instance_id, **update_kwargs)
 
             messages.success(request, _('Instance "%s" successfully updated.')
                              % instance_name)
diff --git a/trove_dashboard/content/databases/views.py b/trove_dashboard/content/databases/views.py
index 097dff9..3ed6fed 100644
--- a/trove_dashboard/content/databases/views.py
+++ b/trove_dashboard/content/databases/views.py
@@ -125,8 +125,10 @@ class UpdateInstanceView(horizon_forms.ModalFormView):
 
     def get_initial(self):
         instance = self.get_object()
+        allowed_cidrs = instance.access.get('allowed_cidrs', ['0.0.0.0/0'])
         return {'instance_id': self.kwargs['instance_id'],
                 'instance_name': instance.name,
+                'allowed_cidrs': ','.join(allowed_cidrs),
                 'datastore_version': instance.datastore.get('version', '')}