diff --git a/github/resource_github_team_repository.go b/github/resource_github_team_repository.go
index e53e4795ca..cf37c10911 100644
--- a/github/resource_github_team_repository.go
+++ b/github/resource_github_team_repository.go
@@ -36,7 +36,7 @@ func resourceGithubTeamRepository() *schema.Resource {
 				Type:         schema.TypeString,
 				Optional:     true,
 				Default:      "pull",
-				ValidateFunc: validateValueFunc([]string{"pull", "triage", "push", "maintain", "admin"}),
+				ValidateFunc: validateTeamRepositoryPermissionFunc,
 			},
 			"etag": {
 				Type:     schema.TypeString,
diff --git a/github/util.go b/github/util.go
index 2b17a5cc54..2012c93bb9 100644
--- a/github/util.go
+++ b/github/util.go
@@ -192,3 +192,40 @@ func validateSecretNameFunc(v interface{}, keyName string) (we []string, errs []
 
 	return we, errs
 }
+
+func validateTeamRepositoryPermissionFunc(v interface{}, keyName string, meta interface{}) (we []string, errors []error) {
+	roleName, ok := v.(string)
+	if !ok {
+		return nil, []error{fmt.Errorf("Expected type of %s to be string", keyName)}
+	}
+
+	roles := []string{"pull", "triage", "push", "maintain", "admin"}
+
+	client := meta.(*Owner).v3client
+	orgName := meta.(*Owner).name
+	ctx := context.Background()
+
+	customRoles, _, err := client.Organizations.ListCustomRepoRoles(ctx, orgName)
+
+	if err != nil {
+		return nil, []error{fmt.Errorf("Error in response from github while checking for existing custom roles. Error: %s", err)}
+	}
+
+	for _, role := range customRoles.CustomRepoRoles {
+		roles = append(roles, *role.Name)
+	}
+
+	valid := false
+	for _, role := range roles {
+		if role == roleName {
+			valid = true
+			break
+		}
+	}
+
+	if !valid {
+		return nil, []error{fmt.Errorf("A role with the name %s does not exist in this GitHub organisation", roleName)}
+	}
+
+	return we, errors
+}
diff --git a/website/docs/r/team_repository.html.markdown b/website/docs/r/team_repository.html.markdown
index e35ebab343..b9af9ac8a5 100644
--- a/website/docs/r/team_repository.html.markdown
+++ b/website/docs/r/team_repository.html.markdown
@@ -44,7 +44,7 @@ The following arguments are supported:
 * `team_id` - (Required) The GitHub team id or the GitHub team slug
 * `repository` - (Required) The repository to add to the team.
 * `permission` - (Optional) The permissions of team members regarding the repository.
-  Must be one of `pull`, `triage`, `push`, `maintain`, or `admin`. Defaults to `pull`.
+  Must be one of `pull`, `triage`, `push`, `maintain`, `admin` or the name of an existing [custom repository role](https://docs.github.com/en/enterprise-cloud@latest/organizations/managing-peoples-access-to-your-organization-with-roles/managing-custom-repository-roles-for-an-organization) within the organisation. Defaults to `pull`.
 
 
 ## Import