如图所示： 

<el-input class="custom-input" placeholder="请输入" prefix-icon="prefix" v-model="form.name" clearable></el-input>

:deep(.custom-input) {
  .el-input__icon {
    display: inline-block;
    width: 40px;
    font-style: normal;
    line-height: 32px;
    color: #3C3C3C;
  }

  prefix {
    position: relative;
    
    &::after {
      content: "名称：";
      white-space: nowrap;
    }
  }
}