The present investigation was carried out to study the performance, heterosis and combining ability in grain sorghum by using line × tester analysis. Twenty-four crosses were obtained by crossing six cytoplasmic male sterile lines (CMS-lines) with four restorers lines (R-lines) at Shandaweel Agric. Res. Station, ARC in 2018 summer season. Thirty five genotypes (24 crosses, their parental lines (10) and the hybrid Shandaweel-305 as check) were evaluated in the summer growing seasons 2019 and 2020 in Shandaweel for days to 50% blooming, plant height, 1000-grain weight and grain yield/plant. The mean squares due to years, genotypes and their partitions crosses, parents and crosses vs parents were highly significant for all studied traits. Also, the interactions between genotypes and their partitions with years were significant or highly significant for all traits. The mean squares due to males, females and their interactions were highly significant for all studied traits. The best female for general combing ability effects (GCA) was ICSB-47 for earliness, BSH-8 for high plant height, BSH-23 for 1000-grain weight and BPOP-15 for grain yield. On the other hand, the best restorer line for GCA effects was RSH-26 for all traits. Meanwhile, the best cross for specific combining ability effects was ASH-23 × MR-812 for earliness, ASH-23 × RSH-26 for high plant height, A POP-15 × Dorado for 1000-grain weight and ASH-8 × RSH-26 for grain yield per plant. Four crosses (APOP-15 ×MR-812, APOP-15× Dorado, ICSA-88003× RSH-26 and ASH-8× RSH-26) had desirable values for heterosis relative to better parent and superior relative to check hybrid for most studied traits. These crosses will be subjected to large-scale field-testing to ascertain their suitability for release as commercial hybrids.