Estrogen is an essential steroid hormone that promotes fish gonad development and maintains reproductive function,contributing to regulate energy metabolism and growth development. Estrogen receptors (ERs) are the key receptor that mediate estrogen regulation in multiple tissues and organs. Therefore,ERs may be related to fish growth and gonadal development. In this study,we cloned the coding sequences (CDS) of estrogen receptor genes in blunt snout bream (Megalobrama amblycephala),including ERα (1 904 bp),ERβ1 (1 842 bp) and ERβ2 (2 609 bp). Through comparing the homology of ERs among different species,we found that the ERs of M. amblycephala share high similarity with carp,goldfish and zebrafish. To analyze the relationship between ERs and gonad and growth,we collected one-year,two-year,and three-year old M. amblycephala,and selected individuals with fast growth (FG) and slow growth (SG) at each age stage. The expression of ERs in the gonad and muscles of M. amblycephala at different ages was analyzed. The results showed that in the early stage of gonadal development,ERa tended to play an important role in growth rather than gonad development. At the metaphase of gonadal development,ERα had an effect on gonad development,and ERβ1 replaced the effect of ERa in growth. After gonadal maturation,the expression of ERα and ERβ1 in the FG group was significantly higher than the SG group,but the expression difference of ERβ1 between FG and SG groups was only shown in males,while ERα affected both males and females. In addition,the expression difference of ERβ2 between FG and SG groups was contrary to that of ERα and ERβ1,which inhibit growth in the early and middle stages of gonadal development. Taken together,ERs could promote the gonads and growth of fish to a certain extent. Meantime,ERα,ERβ1 and ERβ2 might form a complex regulatory system to influence with each other and jointly regulate body growth and gonadal development.