Rainfall calibration device

The utility model discloses a rainfall calibration device, which adopts a first standard metering ball, a second standard metering ball and a third standard metering ball which are equal in horizontal height and have fixed capacity of 10ml, overflow pipes which are respectively connected with the first standard metering ball, the second standard metering ball and the third standard metering ball are arranged above the first standard metering ball, the second standard metering ball and the third standard metering ball to add water, and when the corresponding capacity of water is filled, the water overflows and is discharged. At the moment, the water quantity of three 10ml is well added, the required flow is well adjusted through the flow control valve knob, and then the first water outlet valve knob, the second water outlet valve knob and the third water outlet valve knob are sequentially opened to complete three times of calibration, so that the operation is simplified, and the calibration efficiency is impro