The invention discloses a testing device for simulating water evaporation of bioretention ponds under different meteorological conditions. The testing device comprises a water collection device and a plurality of bioretention ponds, wherein the water collection device is used for collecting runoff rainwater of a roof; the water collection device is connected with a plurality of nozzles through a water supply unit; the nozzles are arranged above the corresponding bioretention ponds; testing packing layers are arranged inside the bioretention ponds; thermometers, hygrometers and an anemograph are arranged on the bioretention ponds; and weighing sensors and water discharge valves are arranged at the bottoms of the bioretention ponds. The testing device is capable of simulating evaporation testing under conditions of different fillers, different plants and different ratios, data is precise and reliable, and instructions can be provided for actual engineering application.