Age and growth are two important biological characteristics of cephalopoda. According to the 3462 short-fin squid Illex argentinus samples collected by the Chinese jigging fishing fleet during 2007, 2008 and 2010, the age, growth and population structure of Illex argentinus were studied based on the microstructure of the statolith. The result indicated the life cycle of Illex argentinusis approximately one year, two hatching groups could be identified (austral winter group and austral autumn group), and there was a sexual dimorphism in the mantle length and body weight growth between different groups. The relationship between age and mantle length (ML) was best described by exponential and linear functions for females and males for austral winter group and exponential and logarithm functions for austral autumn group, respectively. The relationship between age and body weight (BW) was best described by exponential and logarithm functions for females and males for both two groups. The instantaneous relative growth rate of Illex argentisnus tended to be high at young stages, and then decreased with the age increasing, however the absolute growth rate tended to be higher with the age increasing, and the growth rate was different between males and females in the same age stage.