1. 直接写在color数组中

option = {
  color:['#fac858','#e0504b','#e6e9ee'],
  series: 
    {
      type: 'pie',
      radius: ['40%', '70%'],
      data: [
        { value: 1048, name: 'Search Engine', },
        { value: 735, name: 'Direct'},
        { value: 580, name: 'Email' },
      ]
    }
};

2. 在series.data.itemStyle.color中

option = {
  series: 
    {
      type: 'pie',
      radius: ['40%', '70%'],
      data: [
        { value: 1048, name: 'Search Engine',itemStyle:{color:'#fac858'} },
        { value: 735, name: 'Direct',itemStyle:{color:'#e0504b'} },
        { value: 580, name: 'Email',itemStyle:{color:'#e6e9ee'} },
      ]
    }
};