In order to solve the problem of simultaneous monitoring of macro and micro characteristics of rainfall, a piezoelectric effect-based rainfall parameter sensing method is proposed. Firstly, to eliminate the boundary effect of the sensor, a piezoelectric array transducer is used to accurately measure the end momentum of falling raindrops. Then the raindrop size is obtained by using the calibrated response function. Secondly, a raindrop aliasing recognition method based on the true effective voltage signal is proposed to calculate the number of raindrops. Finally, raindrop size distribution is obtained by synthesizing the size and quantity of raindrops. Rainfall and intensity are obtained by accumulating the volume of raindrops. Mathematical simulation and experimental results show that the proposed scheme can automatically and continuously measure and record the size and the number of raindrops, rainfall and real-time rainfall intensity with high measurement accuracy for heavy rain, light rain and micro-characteristics of rainfall.