Abstract: The antimicrobial ingredient (WH-01) of Chaetomium globosum ZH-32, an endophytic fungus from the leaves of Platycladus orientalis, was obtained by bioassay testing of the extraction from the fermentation broth. The compound was identified as chaetoglobosin A by UV, ESI-MS and NMR techniques, as well as by comparing it with the data published previously. Bioassay results showed that WH-01 had strongly inhibitory activities against Bacillus subtilis, Bacillus cereus, Staphylococcus aureuse, and Escherichia coli, and the minimum inhibitory concentration (MIC) values of WH-01 were 3.13, 3.13, 1.56 and 3.13 μg/mL, respectively. Additionally, WH-01 had excellent inhibitory activities against Botrytis cinerea and Sclerotinia sclerotiorum, and the EC50 values were 5.36 and 12.19 μg/mL, respectively.