Abstract: The raindrop spectrum, a high-frequency observational dataset that directly describes raindrop size and quantity, has been widely used for precise evaluation and analysis of raindrop variations across different weather conditions and types. The study utilized raindrop spectrum observation data from 2019 to 2022 in Shaanxi Province. The authors analyzed the overall precipitation characteristics under the influence of five weather circulations, the drop spectra characteristics of rainstorm and non-rainstorm processes, and those of convective precipitation and stratiform precipitation. The results indicate that the contribution of precipitation with a rainfall rate＞5 mm h⁻¹ to total process rainfall varies considerably across different circulation systems. This variation primarily stems from differences in the number concentration and contribution of raindrops within each diameter interval. For example, the southwest airflow type is often characterized by stable precipitation, formed by long-term, high-concentration small raindrops, whereas the northwest airflow type tends to produce intense precipitation, driven by short-term, high-concentration large raindrops. The differences in drop spectrum characteristics between rainstorm and non-rainstorm circulations become more pronounced, with heavy rainfall significantly enhancing raindrop spectral parameters. The variation of number concentration with diameter indicates that the proportion and spectral width of convective precipitation raindrops with a rainfall rate＞5 mm h⁻¹ are generally higher in rainstorms than in non-rainstorms. The distribution range and magnitude of D_m–N_w between convective precipitation and stratiform precipitation are nearly similar, with differences in the location of mean and high-value areas. Compared with similar regions such as Zhaosu, Zhuhai, and Palau Island, most convective precipitation in Shaanxi exhibits oceanic convective precipitation characteristics. A few instances of continental convective precipitation occur in flat, straight airflow weather or northwest airflow weather. Based on this analysis, the study diverges from the traditional Z–R empirical relationship and optimizes the fitting of Z–R precipitation estimation equations for various circulation precipitation types using raindrop spectra. This optimization enhances the accuracy of radar precipitation estimation across different weather scenarios in Shaanxi.