Combining ability is mostly used by breeders to select appropriate parental cultivars to produce the larger progeny of new combinations through their hybridization. The objectives of this research were to estimate general combining ability of parents and specific combining abilities of F1 hybrids, to identify suitable parents and hybrids for yield and its contributing traits. In this study, 18 F1 hybrids obtained by crossing six lines (Ethiopia) with three testers (Brazil) in line X tester mating design during summer season of 2013-14 and were planted in complete randomized block design with two replications during summer season of 2014-15. Among the lines, BELESA 95 proved to be a good general combiner for number of pods per plant, grain yield per plant and pod weight. Majority of the best specific combination for different characters resulted from the crosses among the parents with high X low and low X low GCA effects. Non-additive effects were predominant for number of pods per plant and grain yield, but appreciable additive effects were observed for hundred seed weight, pod weight and primary branches. Non-additive as well as additive types of gene action are more important for soybean improvement.