Abstract: To increase chitinase activity,response surface methodology was used to optimize the fermentation conditions of cold-adapted chitinase by Photobacterium sp. LG-1. The result of Plackett-Burman showed that the important factors influencing chitinase production were fermentation temperature,fermentation time and yeast extract. The optimal fermentation conditions were determined as followed: colloidal chitin 12.0 g/L,yeast extract 4.5 g/L,shaking speed 220 r/min,fermentation temperature 20 ℃,liquid volume 75 mL/250 mL,inoculums dose 1%,pH7.0,and fermentation time 120 h,respectively. Under these conditions,the max enzyme activity of chitinase was 5.10 U/mL.The maximum theoretic value was consistent with mean value of verification test and the chitinase production was increased by 11.50% comparing to that before optimization.It provides a reference for the research on the degradation mechanism of low-temperature chitinase and its application in industry.