In order to determine the flood-prone seasons in various regions of China, and reveal the impact of climate change on flood seasonality, the annual maximum flood peak data of 2719 hydrological stations in China from 1960 to 2020 were collected. The seasonal rules, spatial clustering characteristics, and interannual variation rules of the maximum flood peak occurrence time were analyzed by using cyclic statistical method and cluster analysis method. The results show that the occurrence time of the annual maximum flood peak is highly concentrated, generally from June to September, and gradually delayed from southeast to northwest. According to the flood seasonality, four clusters can be grouped into Guizhou Province and Chongqing(cluster 1), South China (cluster 2), Yunnan Province and other regions (cluster 3), and Qinling Mountains and Huaihe River north (Cluster 4), among which cluster 2 has the most concentrated spatial distribution. The occurrence time of the annual maximum flood peak in cluster 2 and cluster 4 shows a significantly delayed and advanced trend, respectively, while the occurrence time of cluster 1 is basically unchanged.