In order to comprehensively utilize the crayfish shell and reduce the production cost of chitin deacetylase， in this study we used crayfish shell powder as the main component of the medium， and inoculated with Rhodococcus sp. strain 11-3 to produce chitin deacetylase. The crayfish shell powder was firstly proteolytically hydrolyzed； then， supplemental nutrients and environmental conditions were optimized by single factor test， Plackett-Burman design， steepest climbing test and Box-Behnken test. The results showed that 19% crayfish shell powder medium was treated with alkaline protease at 5 U/mg for 4 h， supplemented with 1% sucrose， 0.25% ammonium sulphate and 0.75% corn syrup. Rhodococcus was introduced into the medium at a seeding rate of 3%， and cultured at 200 r/min for 2.5 days. The enzyme production activity reached 2 723 U/mL， which was about 53 times higher than the initial crayfish shell powder medium. Therefore， Rhodococcus in the obtained medium having crayfish shell powder as a main component can produce chitin deacetylase having high enzyme activity. It provides a new way for the comprehensive utilization of crayfish shells， and also provides a research basis for the future direct extraction of chitosan from crayfish shells using biological methods.