The work herein analysed esterifying enzyme production activity of molds,which were isolated from the fermentation environment.Among the 135 strains,40 strains were identified to produce esterifying enzyme.Most(34 strains) of them came from air of fermentation workshop;then from Zaopei(4 strains);the others were from Quyao(1 strain) and air of Qu workshop(1 strain).The phylogenetic relationships of these 40 strains were analyzed based on the ITS nu-rDNA.Results showed that they were consisted of 6 genera including Penicillium,Aspergillus,Emericella,Rhizopus,Cladosporium,Mucor,and 19 stains and 13 strains belonged to Penicillium and Aspergillus,respectively.The study not only indicated that a large number of esterifying enzyme production molds existed,but also revealed a high diversity in Yibin strong-flavor liquor fermentation environment.