diff --git a/internal/backend/remote-state/s3/backend.go b/internal/backend/remote-state/s3/backend.go
index 959f40f8a7..bc47c33af6 100644
--- a/internal/backend/remote-state/s3/backend.go
+++ b/internal/backend/remote-state/s3/backend.go
@@ -217,6 +217,16 @@ func (b *Backend) PrepareConfig(obj cty.Value) (cty.Value, tfdiags.Diagnostics)
 		return obj, diags
 	}
 
+	if val := obj.GetAttr("bucket"); val.IsNull() || val.AsString() == "" {
+		diags = diags.Append(tfdiags.AttributeValue(
+			tfdiags.Error,
+			"Invalid bucket value",
+			// `The "bucket" attribute value must not be empty.`,
+			`"bucket": required field is not set`,
+			cty.Path{cty.GetAttrStep{Name: "bucket"}},
+		))
+	}
+
 	if val := obj.GetAttr("key"); val.IsNull() || val.AsString() == "" {
 		diags = diags.Append(tfdiags.AttributeValue(
 			tfdiags.Error,
@@ -237,7 +247,7 @@ func (b *Backend) PrepareConfig(obj cty.Value) (cty.Value, tfdiags.Diagnostics)
 		))
 	}
 
-	if val := obj.GetAttr("region"); val.IsNull() {
+	if val := obj.GetAttr("region"); val.IsNull() || val.AsString() == "" {
 		if os.Getenv("AWS_REGION") == "" && os.Getenv("AWS_DEFAULT_REGION") == "" {
 			diags = diags.Append(tfdiags.AttributeValue(
 				tfdiags.Error,
diff --git a/internal/backend/remote-state/s3/backend_test.go b/internal/backend/remote-state/s3/backend_test.go
index 6662ad4dfe..b9c8e51d60 100644
--- a/internal/backend/remote-state/s3/backend_test.go
+++ b/internal/backend/remote-state/s3/backend_test.go
@@ -614,11 +614,17 @@ func TestBackendConfig_PrepareConfigValidation(t *testing.T) {
 			b := New()
 
 			_, valDiags := b.PrepareConfig(populateSchema(t, b.ConfigSchema(), tc.config))
-			if valDiags.Err() != nil && tc.expectedErr != "" {
-				actualErr := valDiags.Err().Error()
-				if !strings.Contains(actualErr, tc.expectedErr) {
-					t.Fatalf("unexpected validation result: %v", valDiags.Err())
+			if tc.expectedErr != "" {
+				if valDiags.Err() != nil {
+					actualErr := valDiags.Err().Error()
+					if !strings.Contains(actualErr, tc.expectedErr) {
+						t.Fatalf("unexpected validation result: %v", valDiags.Err())
+					}
+				} else {
+					t.Fatal("expected an error, got none")
 				}
+			} else if valDiags.Err() != nil {
+				t.Fatalf("expected no error, got %s", valDiags.Err())
 			}
 		})
 	}
@@ -666,11 +672,17 @@ func TestBackendConfig_PrepareConfigWithEnvVars(t *testing.T) {
 			})
 
 			_, valDiags := b.PrepareConfig(populateSchema(t, b.ConfigSchema(), tc.config))
-			if valDiags.Err() != nil && tc.expectedErr != "" {
-				actualErr := valDiags.Err().Error()
-				if !strings.Contains(actualErr, tc.expectedErr) {
-					t.Fatalf("unexpected validation result: %v", valDiags.Err())
+			if tc.expectedErr != "" {
+				if valDiags.Err() != nil {
+					actualErr := valDiags.Err().Error()
+					if !strings.Contains(actualErr, tc.expectedErr) {
+						t.Fatalf("unexpected validation result: %v", valDiags.Err())
+					}
+				} else {
+					t.Fatal("expected an error, got none")
 				}
+			} else if valDiags.Err() != nil {
+				t.Fatalf("expected no error, got %s", valDiags.Err())
 			}
 		})
 	}