The invention relates to a leech culture pond capable of automatically draining water. The leech culture pond comprises a pond body. A water inlet pipe is fixedly installed above the left side of the pond body. An L-shaped water outlet pipe is installed below the right side of the pond body through a bearing. A lower belt pulley is installed at the right portion of the water outlet pipe. A belt is installed on the lower belt pulley. An upper belt pulley is installed at the upper portion of the belt. The upper belt pulley is connected with a motor fixedly installed on the pond body. A filter net is installed inside the water outlet pipe. The leech culture pond is convenient to use, on the basis that water can be conveniently drained out by arranging the water outlet pipe, due to motor drive and belt transmission, the water outlet pipe can be automatically controlled to change position above or under water, and then the effect of automatically controlling water outflowing is achieved; the leech culture pond has the advantages of facilitating water changing culture and saving manpower.