Salinity is one of the major stress between the abiotic stresses for plants worldwide. This study aimed to investigate and evaluate variations in salt tolerance of four tomatoesgenotypes (Super strain B, Castle Rock, Edkawy and Advantage II) under laboratory conditions using different concentration of NaCl. The cotyledon explants were cultured in MS media containing 0.5 mg/l BA and 0.5 mg/l Kin under different concentration of NaCl (0.0, 3.0, 6.0, 8.0 and 11.0 gm/L). Cotyledon culturability traits such as the percentage of each callus induction, plant regeneration, rooting, number of shoots, shoot length, roots number, root length and the plantlets number were measured to evaluate the salinity tolerance. All growth traits decreased with increasing of NaCl concentration in the culture media. The results suggested that the Edkawy genotype was the best for the percentage of plant regeneration (79.33%), percentage of rooting (54.66%), length of the shoot (7.46 cm), length of the root (5.73 cm) and callus fresh weight (2.72 gm) compared with the other genotypes under different levels of NaCl. Super Strain B and Castel Rock genotypes gave the highest shoots number and plantlets number (13.00 ,13.06 and 4.66 ,4.00 respectively). Advantage II genotype gave the lowest values for almost traits except the percentage of callus induction which was the best value (90%). Super Strain B genotype appeared the best in the percentage for callus induction (53.33%), percentage of plant regeneration (36.66%) and length of the shoot (4.66 cm) under the highest salt concentration (11.0 gm/L).