Abstract: Family selection has emerged as a crucial tool for selective breeding in aquaculture. The current artificial selection for Japanese scallop (Mizuhopecten yessoensis) predominantly focused on the apparent characters, e.g. growth, shell color and survival rate. Little studies of selective breeding were based on nutritional value of adductor muscle. The present study investigated the growth performance, the fatty acid composition, the content of carbon and nitrogen and C/N ratio of adductor muscle in distinct selective breeding families of M. yessoensis and explored the correla-tion between C/N ratio and fatty acid content. The results demonstrated that the growth features of the families 25#, 54# and 19# were superior to those of 32#, 87# and 93# (P<0.05). No significant difference of the total major fatty acids was observed between distinct families, but the relative abundance of the major fatty acids was obviously diffe-rent between distinct families as PUFA>SFA>MUFA. The amounts of EPA and DHA based on dry weight of adductor muscle in M. yessoensis varied from 3.59 to 4.09 mg/g, and from 3.03 to 3.46 mg/g, respectively. The relative abun-dance of both EPA and DHA ranged between 47.19% and 49.32% of the total fatty acids. Moreover, the content of carbon and nitrogen of adductor muscle in distinct families of M. yessoensis remained constantly with (39.21±0.04)% and (10.62±0.16)%, respectively. The C/N ratio was (3.70±0.06). The further correlation analysis showed that the C/N ratio was positively related to the growth of adductor muscle in distinct families. On the contrary, a prominently negative correlation existed between the C/N ratio and the content of TFA, SFA, PUFA, EPA or DHA with the most evident one between C/N ration with DHA. Our results indicated that the fatty acid composition, the content of C and N and the C/N ratio of adductor muscle could be used for selective breeding of M. yessoensis. These findings provide important implications for the broad development of the selective breeding in scallops.