SUMMARYThis research was carried out for evaluating the morphogenesis responses of hypocotyls thin cell layers (TCL) of Lycopersicon esculentum Mill with various concentrations of NAA-Naphthaleneacetic Acid (NAA) and two types of cytokinins. The TCLs (0.1-0.5 mm) of hypocotyls were cultured to MS medium, containing various concentrations of NAA (0, 0.3, 0.5, 1 and 1.5mg/l) with 2 mg/l of BAP and kin. The obtained callus was transferred to the regeneration medium. The results showed that callus induction occurred in the all cultures containing auxin and cytokinin. But, callus induction was not observed on the medium containing only BAP and kin. So, the presence of auxin is essential for callus induction. The percentage of root and shoots, callus weight and diameter with BAP significantly differ in various concentrations of NAA. BAP and NAA concentrations of 2 mg/l and 1.5 mg/l of had maximum effects on callus weight and diameter, respectively. However, the maximum shoots were observed with the concentration of 1 mg/l of NAA. Different concentrations of NAA with kin significantly affected callus weight and diameter root and shoots. The maximum callus weight and diameter as well as percentage of shoots happened in NAA concentrations of 2 mg/l and 1 mg/l kin, respectively. The maximum number of root was observed with the concentrations of 2 mg/l kin and 0.3 mg/l NAA. The comparison between media containing BAP and kin showed that responses were better on the medium containing kin. Also, the amounts of roots, shoots and callus fresh weight were higher than those of BAP.