To implement a GridView with rounded corners for its items in Flutter, you can use a combination of GridView.builder and ClipRRect

import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: GridViewRoundedExample(),
    );
  }
}

class GridViewRoundedExample extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('GridView with Rounded Corners'),
      ),
      body: GridView.builder(
        padding: EdgeInsets.all(8.0),
        gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
          crossAxisCount: 2,
          crossAxisSpacing: 8.0,
          mainAxisSpacing: 8.0,
        ),
        itemCount: 10,
        itemBuilder: (context, index) {
          return ClipRRect(
            borderRadius: BorderRadius.circular(12.0),
            child: Container(
              color: Colors.blue, // Replace with your item content
              child: Center(
                child: Text(
                  'Item $index',
                  style: TextStyle(
                    color: Colors.white,
                    fontSize: 20.0,
                  ),
                ),
              ),
            ),
          );
        },
      ),
    );
  }
}