Abstract: Based on surface observation data from 2013 to 2023, the spatiotemporal distribution and evolution characteristics of nocturnal rainfall frequency in the Daba Mountains are statistically analyzed. The results show that: Spatially, the nocturnal rainfall frequency gradually decreased from southwest to northeast, with precipitation peak times progressively delayed along the direction. Nocturnal rainfall is most pronounced in spring, with an average frequency exceeding 60%, while relatively lower in winter. The concentrated precipitation periods and timing of maximum hourly precipitation shift later with seasonal progression, being earliest in spring and latest in winter. Nocturnal rainfall events occur most frequently in autumn, while rainfall intensity peak in summer. Over the past 11 years, the nocturnal rainfall frequency in Daba Mountains has shown an increasing trend at a rate of 0.3%/year. The increase in post-midnight precipitation proportion during summer is the main contributor to the rising nocturnal rainfall frequency. Additionally, with seasonal changes, the proportion of post-midnight precipitation gradually decrease while morning precipitation proportion increase.