Study was jointly done at Sustainable Development of Environment and Management its Projects Department, Environmental Studies and Research Institute, University of Sadat City and Rice Research and Training Center (RRTC), Sakha Research Station, Kafr EL-Sheikh, Agricultural Research Center (ARC), Egypt during 2018 and 2019. Four of the most important local varieties and lines were selected for yield and quality,i.e, Sakha 101, Sakha 104, and GZ 9461-4-2-3-1 and Giza 178 were used as lines and 4 testers. They are IRBL 7-M, IR12N245, IR12G3239 and Sakha Super300 in Line X Tester mating design. Sixteen new combinations developed from crossing four lines by four testers were assessed for the extent of combining ability effects, heterosis and genetic parameters for yield and related traits. The data recorded on seven yield characters showed highly significant differences among genotypes; parents, parents vs. crosses, crosses, lines, testers and line × tester for the yield and its components. Estimates of the variance, ratio of general and specific combining ability and degree of dominance indicated the importance of non-additive gene effect for all studied traits. Within lines; Sakha 101, GZ 9461-4-2-3-1 and Giza 178 recorded the best general combining ability effects (GCA) for most of the studied traits. Among testers; IR12G3239 and Sakha Super300 were observed to be good general combiners for most of the studied characters. The cross combinations of GZ 9461-4-2-3-1 x IR12G3239, Giza178 x IR12G3239 and Sakha101 x IRBL 7-M were observed to be good specific cross combinations for grain yield and most of its related traits due to highly significant specific combining ability effects (SCA) and heterotic effects. High broad and narrow sense heritability estimates were observed for most studied traits. Correlation estimates revealed that yield per plant correlated positively and significantly with each of number of panicles per plant, panicle length, panicle weight and number of filled grains per panicle.