diff --git a/.changelog/35541.txt b/.changelog/35541.txt
new file mode 100644
index 00000000000..33dc8a8b4ad
--- /dev/null
+++ b/.changelog/35541.txt
@@ -0,0 +1,3 @@
+```release-note:bug
+resource/aws_dms_event_subscription: Mark `source_ids` as Optional. This fixes a regression introduced in [v5.31.0](https://github.com/hashicorp/terraform-provider-aws/blob/main/CHANGELOG.md#5310-december-15-2023)
+```
\ No newline at end of file
diff --git a/internal/service/dms/event_subscription.go b/internal/service/dms/event_subscription.go
index e9226398b07..f745a0de5a5 100644
--- a/internal/service/dms/event_subscription.go
+++ b/internal/service/dms/event_subscription.go
@@ -74,7 +74,7 @@ func ResourceEventSubscription() *schema.Resource {
 			"source_ids": {
 				Type:     schema.TypeSet,
 				Elem:     &schema.Schema{Type: schema.TypeString},
-				Required: true,
+				Optional: true,
 				ForceNew: true,
 			},
 			"source_type": {
@@ -103,12 +103,15 @@ func resourceEventSubscriptionCreate(ctx context.Context, d *schema.ResourceData
 		Enabled:          aws.Bool(d.Get("enabled").(bool)),
 		EventCategories:  flex.ExpandStringSet(d.Get("event_categories").(*schema.Set)),
 		SnsTopicArn:      aws.String(d.Get("sns_topic_arn").(string)),
-		SourceIds:        flex.ExpandStringSet(d.Get("source_ids").(*schema.Set)),
 		SourceType:       aws.String(d.Get("source_type").(string)),
 		SubscriptionName: aws.String(name),
 		Tags:             getTagsIn(ctx),
 	}
 
+	if v, ok := d.GetOk("source_ids"); ok && v.(*schema.Set).Len() > 0 {
+		input.SourceIds = flex.ExpandStringSet(v.(*schema.Set))
+	}
+
 	_, err := conn.CreateEventSubscriptionWithContext(ctx, input)
 
 	if err != nil {
diff --git a/internal/service/dms/event_subscription_test.go b/internal/service/dms/event_subscription_test.go
index 45f3d0c15c6..8463287ba3a 100644
--- a/internal/service/dms/event_subscription_test.go
+++ b/internal/service/dms/event_subscription_test.go
@@ -33,16 +33,16 @@ func TestAccDMSEventSubscription_basic(t *testing.T) {
 		Steps: []resource.TestStep{
 			{
 				Config: testAccEventSubscriptionConfig_enabled(rName, true),
-				Check: resource.ComposeTestCheckFunc(
+				Check: resource.ComposeAggregateTestCheckFunc(
 					testAccCheckEventSubscriptionExists(ctx, resourceName, &eventSubscription),
 					resource.TestCheckResourceAttr(resourceName, "name", rName),
 					resource.TestCheckResourceAttr(resourceName, "enabled", "true"),
-					resource.TestCheckResourceAttr(resourceName, "source_type", "replication-instance"),
 					resource.TestCheckResourceAttr(resourceName, "event_categories.#", "2"),
 					resource.TestCheckTypeSetElemAttr(resourceName, "event_categories.*", "creation"),
 					resource.TestCheckTypeSetElemAttr(resourceName, "event_categories.*", "failure"),
-					resource.TestCheckResourceAttr(resourceName, "source_ids.#", "1"),
 					resource.TestCheckResourceAttrPair(resourceName, "sns_topic_arn", snsTopicResourceName, "arn"),
+					resource.TestCheckResourceAttr(resourceName, "source_ids.#", "0"),
+					resource.TestCheckResourceAttr(resourceName, "source_type", "replication-instance"),
 				),
 			},
 			{
@@ -133,12 +133,13 @@ func TestAccDMSEventSubscription_eventCategories(t *testing.T) {
 		CheckDestroy:             testAccCheckEventSubscriptionDestroy(ctx),
 		Steps: []resource.TestStep{
 			{
-				Config: testAccEventSubscriptionConfig_categories2(rName, "creation", "failure"),
+				Config: testAccEventSubscriptionConfig_eventCategories(rName, "creation", "failure"),
 				Check: resource.ComposeTestCheckFunc(
 					testAccCheckEventSubscriptionExists(ctx, resourceName, &eventSubscription),
 					resource.TestCheckResourceAttr(resourceName, "event_categories.#", "2"),
 					resource.TestCheckTypeSetElemAttr(resourceName, "event_categories.*", "creation"),
 					resource.TestCheckTypeSetElemAttr(resourceName, "event_categories.*", "failure"),
+					resource.TestCheckResourceAttr(resourceName, "source_ids.#", "1"),
 				),
 			},
 			{
@@ -147,12 +148,13 @@ func TestAccDMSEventSubscription_eventCategories(t *testing.T) {
 				ImportStateVerify: true,
 			},
 			{
-				Config: testAccEventSubscriptionConfig_categories2(rName, "configuration change", "deletion"),
+				Config: testAccEventSubscriptionConfig_eventCategories(rName, "configuration change", "deletion"),
 				Check: resource.ComposeTestCheckFunc(
 					testAccCheckEventSubscriptionExists(ctx, resourceName, &eventSubscription),
 					resource.TestCheckResourceAttr(resourceName, "event_categories.#", "2"),
 					resource.TestCheckTypeSetElemAttr(resourceName, "event_categories.*", "configuration change"),
 					resource.TestCheckTypeSetElemAttr(resourceName, "event_categories.*", "deletion"),
+					resource.TestCheckResourceAttr(resourceName, "source_ids.#", "1"),
 				),
 			},
 		},
@@ -282,13 +284,12 @@ resource "aws_dms_event_subscription" "test" {
   enabled          = %[2]t
   event_categories = ["creation", "failure"]
   source_type      = "replication-instance"
-  source_ids       = [aws_dms_replication_instance.test.replication_instance_id]
   sns_topic_arn    = aws_sns_topic.test.arn
 }
 `, rName, enabled))
 }
 
-func testAccEventSubscriptionConfig_categories2(rName string, eventCategory1 string, eventCategory2 string) string {
+func testAccEventSubscriptionConfig_eventCategories(rName string, eventCategory1, eventCategory2 string) string {
 	return acctest.ConfigCompose(testAccEventSubscriptionConfig_base(rName), fmt.Sprintf(`
 resource "aws_dms_event_subscription" "test" {
   name             = %[1]q
diff --git a/website/docs/r/dms_event_subscription.html.markdown b/website/docs/r/dms_event_subscription.html.markdown
index 3d53fe93610..d9fffa2110d 100644
--- a/website/docs/r/dms_event_subscription.html.markdown
+++ b/website/docs/r/dms_event_subscription.html.markdown
@@ -34,9 +34,9 @@ This resource supports the following arguments:
 * `name` - (Required) Name of event subscription.
 * `enabled` - (Optional, Default: true) Whether the event subscription should be enabled.
 * `event_categories` - (Optional) List of event categories to listen for, see `DescribeEventCategories` for a canonical list.
-* `source_type` - (Required) Type of source for events. Valid values: `replication-instance` or `replication-task`
-* `source_ids` - (Required) Ids of sources to listen to.
 * `sns_topic_arn` - (Required) SNS topic arn to send events on.
+* `source_ids` - (Optional) Ids of sources to listen to. If you don't specify a value, notifications are provided for all sources.
+* `source_type` - (Required) Type of source for events. Valid values: `replication-instance` or `replication-task`
 * `tags` - (Optional) Map of resource tags to assign to the resource. If configured with a provider [`default_tags` configuration block](https://registry.terraform.io/providers/hashicorp/aws/latest/docs#default_tags-configuration-block) present, tags with matching keys will overwrite those defined at the provider-level.
 
 ## Attribute Reference