The invention provides a hydrological information monitoring system, which comprises a background server, a drone and multiple monitoring devices, wherein each monitoring device comprises water quality sensors such as a dissolved oxygen sensor, a pH sensor, a chlorophyll sensor and an ammonia nitrogen sensor, and a communication module, a microprocessor, and a buoy. The multiple monitoring devicesare distributed in a water area of an aquaculture site, the information of various kinds of water bodies is acquired in real time and is sent to the background server in a unified mode, the drone ismatched to acquire the radiation image and the optical image of the water area of each monitoring device, the water quality state of the aquaculture site is prejudged according to a preset judgment model, and the aquaculture water body environment can be monitored accurately in real time. Field sampling by a person is not needed, a long-term cycling sampling process is saved especially for a large-scale aquaculture water area, and the efficiency is greatly improved. Besides, the hydrological information monitoring system provided by the invention is simple and economic to execute, and an important reference is provided for fishery aquaculture.