This work was conducted to produce some local tomato hybrids which show high productivity and high quality to meet the desires of consumer and farmer and to lessen the amount of seeds imported from other countries at high prices . The genetic materials used in the present study included 5 cultivars of tomato , this cultivars namely : (1) Marglobe , (2) Peto 86 , (3) Super strain B , (4) Super marmande and (5) Floradade . Plants from each variety were selfed pollinated for three generations to obtain an inbred line from each variety . The work was carried out during two successive years . In 2001 , a half  diallel cross was performed among the five cultivars of tomato (excluding reciprocals) to produce 10 F₁ hybrid seeds . In 2002 the five parents and 10 F₁'s were evaluated during the summer season . The obtained results indicated that heterosis over the better parent gave significant values in most crosses for plant height, number of branches, earliness, number of fruits per plant, early yield per plant and total soluble solids.
     The good combiner parental cultivar and best hybrid combination for each character were estimated according to the best GCA and SCA values . Concerning general combining ability , it was found that Super marmande cultivar was the best combiner for plant height , number of branches , fruit weight , number of locules / fruit and T.S.S . Peto 86 cultivar was the best combiner for earliness, number of fruits / plant , early yield / plant , fruit shape index and flesh thickness . Marglobe cultivar appeared to be the best combiner for fruit set percentage , whereas Floradade was the best combiner for marketable yield / plant . Concerning specific combining ability , Super strain B x Floradade was found to be the best cross for plant height . The cross Super strain B x Super marmande appeared to be the best cross for number of branches / plant , fruit set % and number of fruits / plant . The cross Peto 86 x Floradade was the best combination for earliness . The cross Mrglobe x Peto 86 appeared to be the best combination for early yield / plant and marketable and total yield / plant . It was found also that the cross Peto 86 x Super strain B showed the best cross for both fruit weight and fruit shape index . The cross Marglobe x Super marmande was the best combination for flesh thickness , whereas Marglobe x Floradade cross was the best combination for number of locules / fruit . The cross Peto 86 x Super marmande reflected the best combination for T.S.S .
     Additive gene effects appeared to be more important than non additive gene effects as reflected on the high estimated of GCA variances relative to those of SCA variances for each of earliness and fruit shape index . Whereas it was found that non-additive gene effects appeared to play important roles than additive effects for plant height , number of branches , fruit set % , number of fruits , early yield , marketable yield , total yield , fruit weight , flesh thickness , number of locules / fruit and T.S.S .Therefore this study may help in improving tomato through hybridization and selection .