Abstract: We established the water yield model for single-phase flow under the consideration of stress sensitivity of coalbed methane wells, then completed the history matching of water yield data of two wells on the basis of the basic physical parameters of a block, and then simulated the effects of four parameters such as stress sensitivity coefficient, permeability, skin factor and wellbore radius on water yield. The results show that the stress sensitivity has important influence on the change of the water yield before the desorption of coalbed methane well, and the water yield curve varies with the stress sensitivity. For a particular coalbed gas well, there is an optimum bottom-hole pressure value under where the water yield is maximum. The greater the stress sensitivity coefficient is, the less water yield is. When the stress sensitivity coefficient is greater than 1, there is an invalid descending pressure section, and the greater the stress sensitivity coefficient is, the longer the invalid descending pressure section is. With the increase of the permeability and the wellbore radius, the daily water yield rate increases and the higher of the permeability and the longer of the radius of the wellbore is, the higher the efficiency of fracturing fluid flowback, and the larger the pressure drop zone is. While the daily water yield decreases with the increase of skin coefficient.