The invention discloses a rain simulating device for lab, which includes bracket, water pump, water converter, and water transmission channel, and valve, sprayer and control device. One inlet and several outlets are arranged on the water converter, the pump is connected with the inlet of the water converter, each inlet of the water converter is connected to the sprayer through valve, transmitting channel. The sprayer is arranged on the bracket through transmitting channel. The device controls the valve to act. The invention uses pump to press, and transmits them to each sprayer through water converter, controls the open quantity, size and spraying time of sprayers through the control device, it can realize real simulation to the natural rain, it has characters of small error, automatic control, wireless remote control.