<el-table
        v-loading="dataListLoading"
        :data="dataList"
        style="width: 100%"
        ref="tables"
        class="tab"
        :row-style="iRowStyle"
        :cell-style="iCellStyle"
        :header-row-style="iHeaderRowStyle"
        border
        :header-cell-style="{
          background: 'rgba(194, 210, 255, 0.3)',
          color: '#040415',
        }"
        @selection-change="dataListSelectionChangeHandle"
        :row-key="getRowsKey"
      >

关键代码：

    :row-style="iRowStyle"

        :cell-style="iCellStyle"

        :header-row-style="iHeaderRowStyle"

  computed: {
    iRowStyle: function ({ row, rowIndex }) {
      return 'height:30px';
    },
    iHeaderRowStyle: function ({ row, rowIndex }) {
      return 'height:30px';
    },
    iCellStyle: function ({ row, column, rowIndex, columnIndex }) {
      return 'padding:0px'
    },
  },

效果：