In this study,the samples of Argentine shortfin squid Illex argentinus were collected by the Chinese squid jigger fleet during January to March in 2010,and the dorsal mantle length(DML)of the samples ranged from 166 mm to 266 mm.The total of 264 pairs of beaks(143 pairs for female and 121 pairs for male)were extracted,and the morphological indices in lower beak were measured,including Lower Hood Length(LHL),Lower Crest Length(LCL),Lower Rostral Length(LRL),Lower Lateral Wall Length(LLWL)and Lower Wing Length(LWL).The stages of beak pigmentation of those samples were checked based on the standard of Stage 0 to Stage 7.Combined with the ontogenesis,maturity stage of I.argentinus and growth of beak,the variation of beak pigmentation stages were preliminarily analyzed.The results showed that Stage 3 was the dominant proportion,accounting for 35.98% of the total samples during January to March.The monthly average level of beak pigmentation increased with the time passage from January to March.The beak pigmentation degrees of the samples increased with the growth of DML and body weight,and there were the significant linear relationships between beak pigmentation degrees and DML,beak pigmentation degrees and body weight(P<0.01).The beak pigmentation degrees had a significant relationship with the sexual maturity stage for female squid(P<0.01),but had not significant relationship for male squid(P>0.05).The differences existed in the relationships between different morphological parameters of beaks(LHL,LCL,LRL,LLWL and LWL)and pigmentation stages,in which the significant relationships with LHL,LLWL and LWL are provided