Biology characteristics（such as mantle length, body weight, gender, sexual maturity and feeding levels） of Japanese common squid （Todarodes pacificus） were analyzed by using collected samples from squid jigging in the Sea of Japan from 2010 to 2013, using SSPS software counting fitting growth and Logistic curve. We stated the annual variability of community structure and composition of T. pacificus in the Sea of Japan. As the research of total sample size of Japanese Common Squid in the Sea of Japan were 388. Results showed that female and male mean mantle length of T. pacificus were 231mm and 230 mm (Table 1). The trunk of the individual advantage length group was 220﹣250 mm (Fig.2). The sex ratio was 0.89 which had no significant differences on 1:1 null hypothesis (Fig.1). The relationship between mantle length and body weight was depicted by the power function with growth parameter b closed to 3(Fig.3 and Fig.4). Logistic curve fitting the size at first maturity, the female was 216.04 mm, and the male was 216.71 mm (Fig.6). The mature rate （Ⅲ, Ⅳ and Ⅴ period） was 78.35% in this study (Fig.5), and the feeding intensity mainly distributed at level 1, 2, 3 based on 5 feeding intensity level(Fig.7). From ANOVA to test the effect of maturity stages on the relationship between mantle length and body weight, the relationship had significant differences (Table 2). Fish were the most frequent food （up to 70%） in the stomach contains, mainly on sardines and lantern fish, then Cephalopods, a little crustacean. Annual variability of community structure of T. pacificus in the Sea of Japan was slight different. Its growth and development is related to the change of the marine environment factors, such as temperature, current, salinity and bait abundance.