The utility model discloses an overflow pipe used for a water pool. The overflow pipe comprises a pipe body and further comprises guide plates, threaded rods, overflow plates and corrugated pipes. The guide plates are fixedly arranged inside an upper end opening of the pipe body. The threaded rods are vertically arranged at the upper end of the pipe body, and connected with the upper end opening. The overflow plates are in an annular shape and arranged on the threaded rods through adjusting nuts. The corrugated pipes are arranged in the upper end opening, the lower ends of the corrugated pipes are connected with the guide plates in a sealing mode, and the upper ends of the corrugated pipes are connected with the overflow plates in a sealing mode. The heights of the overflow plates are adjusted through the adjusting nuts, so that the corrugated pipes are driven to stretch and retract, and the overflow height is adjusted. A flow monitoring device is arranged so that overflow flows can be measured in real time. The opening of a gland can be further monitored in real time through an opening monitor, so that the overflow flows are adjusted according to needs.