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One hundred and twenty randomly selected adult individuals from the same A.irradians concentricus cultured population were divided into 3 groups according to shell length:large group(shell length 4.91-6.02 cm,5.40 ±0.28,n =33),middle group(shell length 4.21-4.88 cm,4.50 ± 0.18,n =49)and small group(3.31-4.18 cm,3.93 ±0.19,n =38),then mixed spawning was carried out.Three mix-spawned F1 progeny of these 3 groups were cultured under the same condition.The effect of parental selection on the growth performance of mix-spawned progeny was examined between three size groups through comparisons of egg number,fertilization rate,hatching rate,juvenile survival rate,survival rates over the nursing,grow-out and reproductive periods,daily growth of shell length and shell height and body weight,aiming at assaying the effect of parental selection on the reproductive,growth and survival performances of mix-spawned F1 progeny,and in turn providing some scientific reference for the selective breeding of the scallop.Results showed that for fertilization rate there were no significant difference between three groups(P ＞ 0.05).In terms of other indices as above,F1 progeny of large-size parents were larger than middle ones(P ＜ 0.05);those of middle-size parents were superior to small-size ones(P ＜ 0.05).Responses to selection of shell height,shell length and wet weight were 2.0 mm,2.3 mm and 2.36 g respectively for progeny of large-size parents;-1.4 cm,-0.9 cm and-1.82 g respectively for progeny of middle-size parents,and -3.6 cm,-3.3 cm and-4.19 g respectively for progeny of small-size parents.Realized heritabilities of shell height,shell length and body weight were 0.253,0.274 and 0.202 respectively for F1 population of large-size parents.The directional parental selection for A.irradians concentricus improved the growth and anti-adversity performance of mix-spawned progeny,showing that higher genetic variation was embraced in present cultured populations of A.irradians concentricus in Beibu bay of China,and the strategy of truncation selection for the selective breeding of A.irradians concentricus was suggested.