Raindrop characteristics, including speed and size of raindrops, in Zhengzhou city of Yellow River basin were analyzed through a natural rainfall on the loess slope. Results showed that the process of natural rainfall belonged to a parabola and counts, size and terminal velocity would increase with the rainfall intensity rising. Besides, the size and terminal velocity of natural raindrops were relatively scattered; In the process of individual rainfall, the terminal velocity and its peak value were mainly focused between 0.8~5m/s and 1m/s, respectively. Size of raindrops were mainly consisted of 0.125-0.5mm, among which the terminal velocity of raindrops with a size of 0.125mm, 0.25mm, 0.375mm, 0.5mm were primarily 0.8-3.4m/s, 0.6-3.4m/s, 0.8-1m/s, 1-1.4m/s, respectively.