Abstract: A survey was conducted on walnut diseases in Dali Prefecture, the main walnut producing area in Yunnan Province, and two strains of dominant pathogens of walnut fungal diseases were identified from the diseases, and the two strains of dominant pathogens were identified morphologically and molecularly. The results showed that the pathogen HTY−6, which caused walnut leaf disease, was Diaporthe eres, and the pathogen HTZ−2, which caused walnut branch disease, was Neofusicoccum parvum; Diaporthe eres grows fastest under continuous light condition, the optimal medium is PDA, the optimal pH is 6, the optimal carbon and nitrogen sources are maltose and peptone; Neofusicoccum parvum grows fastest under continuous light condition, the optimal medium is PDA, the optimal pH is 5, the optimal carbon and nitrogen sources are sucrose and peptone. This study clarified the dominant pathogenic bacteria of walnut diseases in Dali Prefecture, and provided a basis for the control of walnut diseases in Dali Prefecture.