Line x Tester (10x3) analysis of F-1 generation in cowpea expressed highly significant differences among parents and hybrid for days to 50% flowering and days to 1(st) green pod picking. The cross combination Black Seeded x Pusa Komal showed maximum negative heterosis over better parent and mid parent, whereas Kala Zamala X Cowpea-263 was better over standard parent for days to 50% flowering. The crosses, Ramnagar Kala x Arka Garima, Red Seeded x Arka Garima and Red Seeded x Cowpea-263 showed maximum negative heterosis over better parent, mid parent and standard parent, respectively for days to 1(st) green pod picking. The variance due to general combining ability and specific combining ability were highly significant denoting importance of additive and non-additive gene action for both the traits. Additive genetic variance was predominant for days to 50% flowering whereas nonadditive genetic variance governs days to 1(st) green pod picking. The parents NDCP-13, Kala Zamala, Red Seeded, Black Seeded, RCV-7, Cowpea-263 and Pusa Komal were good general combiners for both the traits. The crosses Set. 2-2 x Pusa Komal, Cowpea Local x Arka Garima and Sel. 2-1 x Arka Garima were identified as best specific combiners for days to 50% flowering whereas crosses Set. 2-2 x Pusa Komal, Cowpea Local x Arka Garima and Red Seeded x Arka Garima were good for days to 1(st) green pod picking.