To realize the precipitation particle imaging and measurement in the airborne condition, an imaging and measurement system was developed based on photodiode array. The system is composed of an optical system, a hardware system and a software system. The optical system can shape the laser beam and image the particles. The hardware system is composed of a front-end signal conditioning circuit and an FPGA controlling circuit, and mainly function in the particle image acquisition and signal processing. The software system contains two parts in FPGA and PC respectively, and realize the particle image compression, display and storage. Calibration in laboratory shows that the system’s measurement range is in 60～7400 μm, with a resolution in 60 μm. Field campaign results indicate that the system can meet the requirement of precipitation particle imaging and measurement under the flying condition.