This study surveyed a rapid, efficient and reproducible protocol for in vitro shoot regeneration and rooting by different explants and different concentration of BAP. Due to optimization of shoot regeneration, two media including of MS and modified MS (MS salts with double concentration of CaCl2 and B5 vitamins), different explants such as decapitated embryo axes, epicotyls and cotyledonary nodes and different concentrations of BAP hormone (1, 1.5, 2, 2.5, 3 and 4 mg L-1) in two genotypes (Gachsaran and Flip. 92-12 L) were used. The results showed that modified MS is a suitable medium for in vitro shoot regeneration of lentil. High levels of BAP caused increasing of shoot regeneration in lentil genotypes. Three milligram per liter of BAP induced the highest level of shoot regeneration. In addition, decapitated embryo explants were the best explants for highest shoot regeneration (5.8) (p<0.05). However, increasing of hormone concentration from 2 to 3 and 4 mg L-1 caused decreasing in the number of shoots, so 2 mg L-1 of BAP was best. For rooting, the in vitro-in vivo method of rooting was better than only in vitro method. The shoots regenerated in 2 mg L-1 BAP had higher rooting percentage than the shoots were regenerated in 3 and 4 mg L-1 BAP. These results indicate on the inhibitory effect of high concentration of BAP on root induction. But the genotype didn`t have any significant effect on rooting percentage and length of roots.