Abstract: In the development process of the bottom-water reservoirs in horizontal wells, the production effects in the horizontal wells are severely restricted by the unbalanced producing status of the horizontal section. In order to improve the producing effects of the horizontal sections in horizontal wells in bottom-water reservoirs, the conventional horizontal well testing data are used to perform modern well test interpretation for the target horizontal well, and the effective producing length and the geological and development parameters of the wells are obtained. Then, numerical simulation is used to establish a numerical model to simulate the reservoir production performance. With this method, the producing status of the horizontal section can be obtained and its influences are analyzed. The results show in horizontal Well H, serious bottom water invasion appears in the middle part, both edge and bottom water invasion are serious in the toe-end and the producing status is poor in the heel-end. An optimal solution is proposed, that is adding artificial barriers and controlling watercut, maintaining the liquid production rate at 20 m3/d, meanwhile increasing the water injection volume in neighboring wells and doing selective water plugging