The importance of vegetative traits due to the bio mass during early stages which transform to dry mater at late stage. So, the investigation was undertaken to determine the combining ability effects, heterosis and genetic parameters for some vegetative traits. Egypt during 2018 and 2019 growing summer season. Four of the most important local varieties and lines; Sakha 101, Sakha 104, and GZ 9461-4-2-3-1(leaf blast susceptible) and Giza 178 (leaf blast resistant) used as lines and 4 testers contain resistance genes. They are IRBL 7-M, IR12N245, IR12G3239 and Sakha Super300 in Line X Tester design mating design was conducted and 16 F1 hybrid combinations were developed from the crossing between 4 lines and 4 testers. The data recorded on five vegetative traits showed highly significant differences among genotypes; parents, parents vs. crosses, crosses, lines, testers and line × tester for all studied vegetative traits. The estimates of the variance, ratio of general and specific combining ability and degree of dominance indicated preponderance of non-additive gene effect for each trait. Within lines; GZ 9461-4-2-3-1 recorded the best general combining ability effects (GCA) for most of the studied characters. Among testers; IR12G3239 and Sakha Super300 were observed to be good general combiners for most of the studied characters. The cross Sakha101 x IR12G3239 was observed to be good specific cross combinations for the most studied traits due to highly significant specific combining ability effects (SCA) and heterotic effects. High broad and narrow sense heritability estimates were observed for most traits. Correlation estimates revealed that plant height correlated positively and significantly with each of number of tillers per plant and leaf blast reaction to indicate the importance of selection for semi dwarf genotypes.