The characteristics of raindrops from May to October in 2019 and from June to July in 2020 were analyzed by using distrometers, and the results were also compared with the measured data of 0.1mm and 0.5mm resolution rain gauges calibrated in the experimental field. The raindrop velocity and diameter and the relationship between them were obtained. The distribution of raindrop diameters in different rainfall intensities was investigated. The results show that the raindrops with the highest frequency of about 0.5mm diameter accounts for more than 20%, and the raindrops with diameter less than 0.7mm accounts for about 65% from May to October in 2019. The distribution histogram shows a more obvious double peak phenomenon in moderate and heavy rainfall patterns. With the increase of rainfall intensity, triple peak phenomenon occurs in storm rain pattern while single peak phenomenon occurs in light rain pattern. The frequency of the rainfall intensity less than 0.5mm/min is over 90% from May to October in 2019 and during the rainy season in 2020, which requires the factory calibration of rain gauges under weak rainfall intensity.