Abstract: The paper aims to study the rot of yam during storage. The pathogenic microorganisms causing rot of four yam cultivars after harvest were isolated in this research. The isolated strains were identified by morphological, 18S rRNA sequencing and phylogenetic tree. The results showed that the microorganisms causing rot of yam had high homogeneity with Penicillium sclerotigenum strain, which were determined to be P. sclerotigenum. The growth characteristics of P. sclerotigenum were studied by different pH (3, 5, 7, 9, 11) and different biocontrol agents (EM, Bacillus polysaccharide, Trichoderma harzianum, Bacillus subtilis and Streptomyces microflavus). The results showed that the optimum pH value of P. sclerotigenum was 5-7, and the optimum pH value after cultured 42 h was 5. The Bacillus polysaccharide and S. microflavus had better inhibitory efficacy on P. sclerotigenum.