A study of Line x Tester analysis without parents, analysis of eighteen lines and four testers parents was carried out to identify high heterotic crosses and their relationship in terms of general and specific combining ability (GCA and SCA) in rice in year 2013-14 at Borlaug Crop Research Center of G. B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand (India). Analysis of variance showed highly significant difference among all the characters in case of crosses and Line X Tester effect. In line effect all the traits showed significant difference among all the traits except plant height, percent spikelets fertility and 1000 grain weight, in tester effect except for days to 50% flowering, panicle number per plant and harvest index. The estimates of GCA effects indicated male parent Pant Dhan-4 (1.52**) and UPRI-93-287R (2.76**) were good general combiner for grain yield per plant and other yield contributing traits and among the TGMS lines TGMS-17 (12.80**), TGMS-14 (10.60**) and TGMS-16 (9.80**) were observed to be good general combiner for grain yield per plant and other yield related traits. Cross combinations TGMS-9*Pant Basmati-1 (21.88**), TGMS-14*Pant Dhan-4 (21.28**), TGMS-16*UPRI-93-287R (13.24**), TGMS-18*Pant dhan-12 (10.44**) and TGMS-6*Pant Dhan-4 (10.13**) were found to be good specific combinations for grain yield per plant and other desirable traits and needs to be tested on large scale. Analysis of standard heterosis over standard check Pant Sankar Dhan-1, high heterotic combinations for grain yield per plant were TGMS-14*Pant dhan-4(142.33**), TGMS-16*UPRI-93-287R (119.98**), TGMS-18*UPRI-93-287R (118.80**) and TGMS-9*Pant Basmati-1(110.56**). These heterotic combinations may be used for further breeding programme for getting higher yield.