Disclosed are a novel use of Chi92 protein and a bacterial strain expressing the Chi92 protein. The preservation number of Pichia pastoris provided in the present invention is CGMCC No.7634. Also disclosed are a fermentation product of the Pichia pastoris pPIC9/Chi92, and uses of the fermentation product in the preparation of chitinases, in serving as chitinases, and in the degradation of chitin substrates. Also disclosed are the uses of the Chi92 protein in the preparation of chitinases, in serving as chitinases, and in the degradation of chitin substrates.