该效果主要是依照 bootstrap 的一个样式，class="navbar-fixed-top";
参考网址为：http://v3.bootcss.com/components/#navbar-fixed-top
贴上代码。
1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 2 <html xmlns="http://www.w3.org/1999/xhtml"> 3 <head> 4 <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> 5 <title>无标题文档</title> 6 <script type="text/javascript" src="js/jquery2.0.3.min.js"></script> 7 <script type="text/javascript" src="js/bootstrap.min.js"></script> 8 <link rel="stylesheet" href="css/bootstrap.min.css"> 9 <link rel="stylesheet" href="css/bootstrap-theme.min.css"> 10 <style> 11 .table tr th,.table tr td{ width:25% !important;} 12 </style> 13 </head> 14 15 <body> 16 <nav class="navbar navbar-default navbar-fixed-top" role="navigation"> 17 <div class="container"> 18 <table class="table table-bordered" style="margin-top:9px;"> 19 <tr> 20 <th>dksliesjfd</th> 21 <th>dksliesjfd</th> 22 <th>dksliesjfd</th> 23 <th>dksliesjfd</th> 24 </tr> 25 </table> 26 </div> 27 </nav> 28 <div class="container" style="margin-top:80px;"> 29 <table class="table table-bordered"> 30 <tr> 31 <td>dksliesjfd dsdsdsliesjfd dsdsdssliesjfd dsdsdssliesjfd dsdsdssd</td> 32 <td>时光深处，岁月静好.时光深处，岁月静好.时光深处，岁月静好.</td> 33 <td>dksliesjfd</td> 34 <td>dksliesjfd</td> 35 </tr> 36 <tr> 37 <td>dksliesjfd</td> 38 <td>dksliesjfd</td> 39 <td>dksliesjfd</td> 40 <td>dksliesjfd</td> 41 </tr> 42 <tr> 43 <td>dksliesjfd</td> 44 <td>dksliesjfd</td> 45 <td>dksliesjfd</td> 46 <td>dksliesjfd</td> 47 </tr> 48 <tr> 49 <td>dksliesjfd</td> 50 <td>dksliesjfd</td> 51 <td>dksliesjfd</td> 52 <td>dksliesjfd</td> 53 </tr> 54 <tr> 55 <td>dksliesjfd</td> 56 <td>dksliesjfd</td> 57 <td>dksliesjfd</td> 58 <td>dksliesjfd</td> 59 </tr> 60 <tr> 61 <td>dksliesjfd</td> 62 <td>dksliesjfd</td> 63 <td>dksliesjfd</td> 64 <td>dksliesjfd</td> 65 </tr> 66 <tr> 67 <td>dksliesjfd</td> 68 <td>dksliesjfd</td> 69 <td>dksliesjfd</td> 70 <td>dksliesjfd</td> 71 </tr> 72 <tr> 73 <td>dksliesjfd</td> 74 <td>dksliesjfd</td> 75 <td>dksliesjfd</td> 76 <td>dksliesjfd</td> 77 </tr> 78 <tr> 79 <td>dksliesjfd</td> 80 <td>dksliesjfd</td> 81 <td>dksliesjfd</td> 82 <td>dksliesjfd</td> 83 </tr> 84 <tr> 85 <td>dksliesjfd</td> 86 <td>dksliesjfd</td> 87 <td>dksliesjfd</td> 88 <td>dksliesjfd</td> 89 </tr> 90 <tr> 91 <td>dksliesjfd</td> 92 <td>dksliesjfd</td> 93 <td>dksliesjfd</td> 94 <td>dksliesjfd</td> 95 </tr> 96 <tr> 97 <td>dksliesjfd</td> 98 <td>dksliesjfd</td> 99 <td>dksliesjfd</td> 100 <td>dksliesjfd</td> 101 </tr> 102 <tr> 103 <td>dksliesjfd</td> 104 <td>dksliesjfd</td> 105 <td>dksliesjfd</td> 106 <td>dksliesjfd</td> 107 </tr> 108 <tr> 109 <td>dksliesjfd</td> 110 <td>dksliesjfd</td> 111 <td>dksliesjfd</td> 112 <td>dksliesjfd</td> 113 </tr> 114 <tr> 115 <td>dksliesjfd</td> 116 <td>dksliesjfd</td> 117 <td>dksliesjfd</td> 118 <td>dksliesjfd</td> 119 </tr> 120 <tr> 121 <td>dksliesjfd</td> 122 <td>dksliesjfd</td> 123 <td>dksliesjfd</td> 124 <td>dksliesjfd</td> 125 </tr><tr> 126 <td>dksliesjfd</td> 127 <td>dksliesjfd</td> 128 <td>dksliesjfd</td> 129 <td>dksliesjfd</td> 130 </tr> 131 <tr> 132 <td>dksliesjfd</td> 133 <td>dksliesjfd</td> 134 <td>dksliesjfd</td> 135 <td>dksliesjfd</td> 136 </tr> 137 <tr> 138 <td>dksliesjfd</td> 139 <td>dksliesjfd</td> 140 <td>dksliesjfd</td> 141 <td>dksliesjfd</td> 142 </tr> 143 <tr> 144 <td>dksliesjfd</td> 145 <td>dksliesjfd</td> 146 <td>dksliesjfd</td> 147 <td>dksliesjfd</td> 148 </tr><tr> 149 <td>dksliesjfd</td> 150 <td>dksliesjfd</td> 151 <td>dksliesjfd</td> 152 <td>dksliesjfd</td> 153 </tr> 154 <tr> 155 <td>dksliesjfd</td> 156 <td>dksliesjfd</td> 157 <td>dksliesjfd</td> 158 <td>dksliesjfd</td> 159 </tr> 160 <tr> 161 <td>dksliesjfd</td> 162 <td>dksliesjfd</td> 163 <td>dksliesjfd</td> 164 <td>dksliesjfd</td> 165 </tr> 166 <tr> 167 <td>dksliesjfd</td> 168 <td>dksliesjfd</td> 169 <td>dksliesjfd</td> 170 <td>dksliesjfd</td> 171 </tr> 172 173 <tr> 174 <td>dksliesjfd</td> 175 <td>dksliesjfd</td> 176 <td>dksliesjfd</td> 177 <td>dksliesjfd</td> 178 </tr> 179 <tr> 180 <td>dksliesjfd</td> 181 <td>dksliesjfd</td> 182 <td>dksliesjfd</td> 183 <td>dksliesjfd</td> 184 </tr> 185 <tr> 186 <td>dksliesjfd</td> 187 <td>dksliesjfd</td> 188 <td>dksliesjfd</td> 189 <td>dksliesjfd</td> 190 </tr> 191 <tr> 192 <td>dksliesjfd</td> 193 <td>dksliesjfd</td> 194 <td>dksliesjfd</td> 195 <td>dksliesjfd</td> 196 </tr> 197 <tr> 198 <td>dksliesjfd</td> 199 <td>dksliesjfd</td> 200 <td>dksliesjfd</td> 201 <td>dksliesjfd</td> 202 </tr> 203 <tr> 204 <td>dksliesjfd</td> 205 <td>dksliesjfd</td> 206 <td>dksliesjfd</td> 207 <td>dksliesjfd</td> 208 </tr> 209 <tr> 210 <td>dksliesjfd</td> 211 <td>dksliesjfd</td> 212 <td>dksliesjfd</td> 213 <td>dksliesjfd</td> 214 </tr> 215 <tr> 216 <td>dksliesjfd</td> 217 <td>dksliesjfd</td> 218 <td>dksliesjfd</td> 219 <td>dksliesjfd</td> 220 </tr> 221 </table> 222 </div> 223 </body> 224 </html>
还有一种方法，是 position:fixed; top:0;也是可以固定在顶部。
但是，bootstrap 可以自适应网页，简单快捷。
第二种方法：如下，给每个td,th设置宽度，这样便可以是表的布局样式相同
/* 增加表头固定，表内容 有滚动条 --start*/ table thead{display: block;} table tbody{display: block; height: 300px; overflow: auto;} table thead tr th:nth-child(1){width: 107px;} table thead tr th:nth-child(2){width: 130px;} table thead tr th:nth-child(3){width: 152px;} table thead tr th:nth-child(4){width: 133px;} table thead tr th:nth-child(5){width: 142px;} table thead tr th:nth-child(6){width: 111px;} table thead tr th:nth-child(7){width: 212px;} table thead tr th:nth-child(8){width: 160px;} table tbody tr td:nth-child(1){width: 109px;} table tbody tr td:nth-child(2){width: 132px;} table tbody tr td:nth-child(3){width: 155px;} table tbody tr td:nth-child(4){width: 135px;} table tbody tr td:nth-child(5){width: 144px;} table tbody tr td:nth-child(6){width: 114px;} table tbody tr td:nth-child(7){width: 214px;} table tbody tr td:nth-child(8){width: 145px;}