diff --git a/netbox/dcim/filters.py b/netbox/dcim/filters.py
index 96ecefafd..b8086322d 100644
--- a/netbox/dcim/filters.py
+++ b/netbox/dcim/filters.py
@@ -8,7 +8,9 @@ from netaddr.core import AddrFormatError
 from extras.filters import CustomFieldFilterSet
 from tenancy.models import Tenant
 from utilities.constants import COLOR_CHOICES
-from utilities.filters import NameSlugSearchFilterSet, NullableCharFieldFilter, NumericInFilter, TagFilter
+from utilities.filters import (
+    NameSlugSearchFilterSet, NullableCharFieldFilter, NumericInFilter, TagFilter, TreeNodeMultipleChoiceFilter
+)
 from virtualization.models import Cluster
 from .constants import *
 from .models import (
@@ -49,14 +51,15 @@ class SiteFilter(CustomFieldFilterSet, django_filters.FilterSet):
         choices=SITE_STATUS_CHOICES,
         null_value=None
     )
-    region_id = django_filters.NumberFilter(
-        method='filter_region',
-        field_name='pk',
+    region_id = TreeNodeMultipleChoiceFilter(
+        queryset=Region.objects.all(),
+        field_name='region__in',
         label='Region (ID)',
     )
-    region = django_filters.CharFilter(
-        method='filter_region',
-        field_name='slug',
+    region = TreeNodeMultipleChoiceFilter(
+        queryset=Region.objects.all(),
+        field_name='region__in',
+        to_field_name='slug',
         label='Region (slug)',
     )
     tenant_id = django_filters.ModelMultipleChoiceFilter(
diff --git a/netbox/utilities/filters.py b/netbox/utilities/filters.py
index 40e687077..b0c2b3ec3 100644
--- a/netbox/utilities/filters.py
+++ b/netbox/utilities/filters.py
@@ -4,6 +4,15 @@ from django.db.models import Q
 from taggit.models import Tag
 
 
+class TreeNodeMultipleChoiceFilter(django_filters.ModelMultipleChoiceFilter):
+    """
+    Filters for a set of Models, including all descendant models within a Tree.  Example: [<Region: R1>,<Region: R2>]
+    """
+    def filter(self, qs, value):
+        value = [node.get_descendants(include_self=True) for node in value]
+        return super().filter(qs, value)
+
+
 class NumericInFilter(django_filters.BaseInFilter, django_filters.NumberFilter):
     """
     Filters for a set of numeric values. Example: id__in=100,200,300