Card( color: Colors.grey[900], shape: RoundedRectangleBorder( side: BorderSide(color: Colors.white70, width: 1), borderRadius: BorderRadius.circularOnly(left: 10), ), margin: EdgeInsets.all(20.0), child: Container( child: Column( children: <Widget>[ ListTile( title: Text( 'example', style: TextStyle(fontSize: 18, color: Colors.white), ), ), ], ), ), ),

When Card I always use RoundedRectangleBorder.

Card( color: Colors.grey[900], shape: RoundedRectangleBorder( side: BorderSide(color: Colors.white70, width: 1), borderRadius: BorderRadius.circular(10), ), margin: EdgeInsets.all(20.0), child: Container( child: Column( children: <Widget>[ ListTile( title: Text( 'example', style: TextStyle(fontSize: 18, color: Colors.white), ), ), ], ), ), ),