[Rise]

CRYSIS_STALKER,

<table id="myTable" border="1" width="300">
  <tbody>
    <tr><td>1</td><td>2</td><td>3</td><td>4</td><td>5</td><td>6</td></tr>
  </tbody>
</table>
<input type="button" value="Добавить" onclick="addRows()">

<script>
function addRows() {
	var table = document.getElementById('myTable');
	for (var i = 0; i < 2; i++) {
		var row = table.insertRow(-1);
		for (var j = 0; j < 6; j++) {
			row.insertCell(-1).innerHTML = i + '-' + j;
		}
	}
}
</script>