The present study was carried out at the experimental farm of the Rice Research and Training Center (RRTC)., Sakha, kafrelsheikh, during 2014 and 2015 rice growing seasons to study the inheritance of some quantitative characters using a half diallel cross among eight rice parental genotypes namely; Sakha 102, Giza 179, Sakha 105, Sakha 106, GZ 8710, GZ 1368, Wab 56 and IET 1444. The parents and their F1 crosses were evaluated under normal and stress irrigation. Days to heading, plant height, flag leaf Area, chlorophyll content, relative water content, panicle length, number of panicles/plant, 100-kernel weight, sterility percentage and grain yield/plant were estimated. Highly significant mean squares were obtained for genotypes, parents and their crosses in all studied characters. The interactions of genotypes, parents and crosses with environments (irrigation) were detected to be highly significant for studied traits. Mean squares of general combining ability (GCA) and specific combining ability (SCA) and the interaction between environment and each of GCA and SCA were highly significant for all studied characters, indicating the importance of additive and non-additive genetic variances in determining the performance of these characters. The parental genotypes; Giza 179 and GZ 8710 were good combiners for panicles numbers/plant, 100-grain weight, sterility percentage and grain yield / plant. The crosses; (GZ 1368 × IET 1444), (Giza 179 × GZ 8710), (Sakha 102 × IET 1444) and (Giza 179 × Sakha 106) were superior on the basis of specific combining ability effect.