Abstract: Application of postbiotics of inactivated Lactobacillus casei I0B-P 9 in blood glucose reducing is provided in this disclosure. Application of inactivated I0B-P9 fermented postbiotics to preparation of article for relieving diabetes is provided, in which Lactobacillus casei I0B-P9 is preserved in China General Microbiological Culture Collection Center, with a preservation number of CGMCC No. 24195. Lactobacillus casei I0B-P9 strain obtained in the disclosure has high activity, and postbiotics of Lactobacillus casei I0B-P9 obtained in the disclosure can effectively delay and control occurrence and development of type II diabetes, and can be used for preparing products for diabetics.