Abstract: To prevent and control the large-scale stem base rot of sweet potato, 127 samples of stem base rot were collected from 51 villages (disease areas) in 11 counties and urban areas of Zhejiang during 2015-2018, and the isolation and identification of pathogen and the prevention and control test of agentia were carried out for 3 consecutive years (2016-2018). The results showed that: there were 8 identified pathogens, including Dickeya dadantii, Sclerotium rolfsii, Fusarium verticillioides, F. solani, F. oxysporum, Diaporthebatatas, Phomopsis destruens and F. javanicum, and the composition and distribution of pathogenic bacteria varied in different areas, and the disease samples were generally caused by multiple pathogenic bacteria. The prevention and control test of agentia showed that: the utilization of carbendazim or carbendazim combined with mancozeb and carbendazim combined with streptomycin sulfate had obvious effects on prevention and control of stem base rot of sweet potato, but the application concentration should be higher than recommended, especially the application concentration of carbendazim 50%WP should not be more than 300 times, and the effect was better when the application concentration was 100 times. This study identifies the pathogenic bacteria of stem base rot of sweet potato, and determines the agentia types and concentrations for prevention and control the disease.