diff --git a/internal/services/automation/automation_account_resource.go b/internal/services/automation/automation_account_resource.go
index 8449ea619f2e..85ca31d8a467 100644
--- a/internal/services/automation/automation_account_resource.go
+++ b/internal/services/automation/automation_account_resource.go
@@ -86,7 +86,7 @@ func resourceAutomationAccount() *pluginsdk.Resource {
 
 						"key_vault_key_id": {
 							Type:         pluginsdk.TypeString,
-							Required:     true,
+							Optional:     true,
 							ValidateFunc: keyVaultValidate.NestedItemIdWithOptionalVersion,
 						},
 					},
diff --git a/website/docs/r/automation_account.html.markdown b/website/docs/r/automation_account.html.markdown
index a4baf617ae5d..9cd1ae69aa6e 100644
--- a/website/docs/r/automation_account.html.markdown
+++ b/website/docs/r/automation_account.html.markdown
@@ -72,7 +72,7 @@ An `encryption` block supports the following:
 
 * `key_source` - (Optional) The source of the encryption key. Possible values are `Microsoft.Automation` and `Microsoft.Keyvault`.
 
-* `key_vault_key_id` - (Required) The ID of the Key Vault Key which should be used to Encrypt the data in this Automation Account.
+* `key_vault_key_id` - (Optional) The ID of the Key Vault Key which should be used to Encrypt the data in this Automation Account. Required when `key_source` is set to `Microsoft.Keyvault`.
 
 ---