Abstract: Strain A and B were isolated from the surface of the cantaloupe(Cucumis melo L.),which was further identified by the microscopic morphological observation,phenotypic characteristics and molecular methods. Strain A used the 72 kinds of carbon sources,including dextrin,D-galactose,D-gluconic acid,maltose,glycogen,L-rhamnose,L-sorbose,L-lactic acid and etc.. ITS rDNA sequence of strain A showed 99% homology with Fusarium oxysporum f. sp. melonis with the branch length of 0.00.Strain B used 54 kinds of carbon sources,including L-arabinose,D-fructose,glycerol,sucrose,xylitol and etc.. ITS rDNA sequence strain B showed 100% homology with Alternaria alternata with the branch length of 0.00. Therefore,strain A and B was supposed to be Fusarium oxysporum f. sp. melonis and Alternaria alternata,respectively.