Abstract: In the southwest China, most of the water is transferred from the reservoir through canals for agricultural irrigation.The water temperature in reservoirs is stratified, making the water temperature in the reservoir lower than the natural water temperature.Low temperature water will have adverse effects on the growth and development of crops, so measures should be taken to improve the irrigation water temperature.The water temperature in the first phase of the main canal of Xiangjiaba irrigation area was studied, the feasibility of two measures, sunning water pool and stoplog gate, were also analyzed.It is shown that the time of low temperature water in Xiangjiaba irrigation area is mainly from April to June, and the maximum temperature drop is 3.10 ℃.The water temperature at the head of the lateral canal is 16.70 ～ 17.50 ℃ after heated in the sunning water pool, which is basically consistent with the temperature of 16.6～17.5 ℃ through stoplog gate.The heating effect of sunning water pool is basically the same as the stoplog gate, but the total static investment of sunning water pool is 58.23 million CNY and that of stoplog gate is 210.513 38 million CNY,so the sunning water pool is more economic.The established Tangba in the irrigated area was used to increase the temperature of the channel′s low-temperature water with the maximum increase of 1.47 ℃,which could greatly alleviate the problem of low-temperature water.