The invention provides a siphoning device for high-precision rainfall response process. The siphoning device is arranged between an internal rain bearer in a rainfall meter and a metering tipping bucket; the siphoning device comprises a main body part, a siphoning body, and an intermediate part; the main body part is fixedly arranged at the bottom of the rain bearer, the siphoning body is fixedlyarranged on the main body part, and siphoning inlets are arranged at two sides of an upper part of the siphoning body, and a siphoning outlet is arranged at the bottom thereof, and the siphoning inlets are located in the main body part after the siphoning body is installed; the intermediate part is fixed on the siphoning body in the main body part, a cavity with an opened bottom surface is arranged in the intermediate part, the siphoning inlets are located in the cavity, and the intermediate part is used for forming the gaps between the inner sidewall of the cavity and the siphoning body and between the outer sidewall of the siphoning body and the inner sidewall of the main body, and intermediate part is communicated with the gaps at the bottom of the main body part through the bottom surface of the intermediate part. An upper tipping bucket of the traditional dual-layer rainfall meter of the meteorological department is replaced with the siphoning device, the natural raininess real-time change value is stabilized as the fixed value and flows into the tipping bucket, thereby greatly improving the measurement precision of the rainfall meter.