Flutter card top radius is covered by Image

Don't use clipBehavior: Clip.antiAliasWithSaveLayer if you really care about the performance. Use a Container or a DecoratedBox with a BorderRadius as mentioned in chemamolins'answer. Refer to Performance best practices

You can set clipBehavior for Card:

Card(
      clipBehavior: Clip.antiAliasWithSaveLayer, ...

Or you can wrap your image in ClipRRect

ClipRRect(
  borderRadius: BorderRadius.vertical(top: Radius.circular(4.0)),
  child: Image.network(...),
)

You need to put your image in a Container or a DecoratedBox and set the BorderRadius on the BoxDecoration.

     children: <Widget>[
        .....
        Container(
          width: double.maxFinite,
          height: 220.0,
          decoration: BoxDecoration(
            borderRadius:
                BorderRadius.vertical(top: Radius.circular(5.0)),
            image: DecorationImage(
              image: NetworkImage(
                  'https://img.zcool.cn/community/012157578c405f0000012e7e69e7cd.jpg@1280w_1l_2o_100sh.jpg'),
            fit: BoxFit.cover,
            ),
          ),
        ),
        ...
      ]

You can put the image in Material and set the Border Radius and Clip Behaviour.

    Material(
            color: Colors.white,
            borderRadius: BorderRadius.circular(10.0),
            elevation: 2.0,
            clipBehavior: Clip.antiAliasWithSaveLayer,
            type: MaterialType.transparency,
            child: Image.asset(
              "images/user.png",
              height: 150,
              width: double.infinity,
              fit: BoxFit.cover,
            ),
          ),