One hundred and twenty hybrids generated from crossing three cytoplasmic male sterile lines with 40 testers were studied along with parents for combining ability and gene action involved in expression of characters in rice. The ratio of gca and sca variance was less than unity for all the characters also indicated preponderance of non-additive genetic variance and suggested good prospects of the exploitation of variation through hybrid breeding. Amongst the parental lines, PMS 10A, NLR 40024, NLR 34303, PS 4, PS 5, WGL 32100, NLR 20104 and Srikakulam sannalu were found to be good general combiners which can be taken up to generate desirable segregates for further selection. The crosses PMS 3A x NLR 33636, APMS 6A x NLR 34242, APMS 6A x NLR 33671, APMS 6A x MTU 1001, APMS 6A x NLR 145, PMS 10A x NLR 3402, PMS 10A x Sumati and PMS 10A x CR 1001 were identified as most promising hybrids for grain yield plant-1 and their components which could be used for exploitation of heterosis for yield.