In order to clarify the combining ability and genetic effects of ear-related traits in maize, according to NC II genetic mating design, 9 traits of 20 maize inbred lines (9 female parents and 11 male parents) were analyzed.of the general combining ability(GCA), special combining ability(SCA), the broad-sense heritability(h2b) and the narrow-sense heritability(h2n) .The results showed that five inbred lines, namely JZF5, JZF2, JZM10, JZM5 and JZM3, were beneficial significant or extremely significant in GCA of multiple traits. The top 5 hybrid combinations of SCA in kernel weight were JZF5*JZM4, JZF2*JZM1, JZF8*JZM5, JZF6*JZM5, JZF7*JZM5, one of their parents had a very significant positive GCA for grain weight, suggesting that both GCA and SCA effects should be taken into account in hybrid combinations. The additive genetic variance of ear length, bald tip length, grain number per row, row number and water content accounted for more than 70%, and kernel weight accounted for 35.7%, which was mainly composed of non-additive genetic variance. For the h2b, water content > bald tip length > row number > ear length > kernel weight > grain number per row > cob weight > ear width > 100-grain weight, in which bare tip length and row number is more than 60%, and water content is more than 70%. For the h2n, bald tip length > water content > ear row number > ear length > grain number per row> cob weight > ear width > 100-grain weight >kernel weigh, the h2n of bald tip length, water content and ear row number is more than 50%, suitable for early generation selection; the lowest h2n of100-grain weight and kernel weight, 22.8% and 19.7% respectively, which was not suitable for selection in early generations. In this study, some traits of the subjects deviation to male parents,which suggested more attention should be paid to the important effects of male parents on ear-related traits of maize hybrids.