We studied the water balance of Punica granatum under different conditions of soil moisture management in the micro-catchment afforestation experimental site in the Yuanmou dry-hot river valley.The result shows that the water input of the tree strips of catchment system depends on rainfall and slope runoff,which contribute(90.2)% and(9.8%) respectively,and the water output relies on evapotranspiration.The soil water storage under all the conditions has surplus from May to November.Both the evapotranspiration amount and the water surplus amount under different soil moisture conditions are different.When soil water contents are controlled at 10.08%,(11.63)%,13.23%,14.79%,16.85% and 19.14% levels,the total evapotranspiration amounts are 44.5%,(60.8)%,67.0%,82.0%,85.4% and 87.0% of the water input,and the water surplus amounts are 55.5%,(39.2)%,33.0%,18.0%,14.6% and 13.0%,respectively. It shows that the evapotransiration amouat increases with the increase in soil water content,however,the water surplus amount decreases with the increase in soil water content.The correlation between Punica granatum growing state and soil moisture state is significant.Good soil water condition is beneficial to the growth of Punica granatum and the best soil water content range for it is 14%～15% in terms of water-saving in dry-hot river valley.