Lilium longiflorum L. is one the most valuable bulbous flower in the world. As far as the conventional methods to propagate the L. longiflorum is time-consuming, therefore offering an economical method to make an efficient production in the short time could be interesting for producers. Accordingly, micropropagation in bulb plants as an alternative to the conventional methods for vegetative propagation attracts more attention due to its advantages. Here we studied the influence of plant growth regulators on the growth characteristics of Lilium cv. Tresor. The first experiment was set up as a factorial experiment based on the completely randomized design to evaluate the interactive effect of NAA and BA on Lilium's explants. The second experiment was performed based on the completely randomized design to investigate the effect of PBZ on its explants. Results showed that in the first experiment the highest number of balblet obtained in the concentration of 0.5 and 1 mg/L of NAA. Also the maximum and the minimum number of the shoot were developed in 1.5 mg/L BA and 1.5 m/L NAA respectively. The best combination of plant growth regulators for root formation was observed on 1 mg/L NAA with 0.1 mg/L BA. The regeneration percentage of explants were raised by increasing the NAA concentration. In the second experiment the maximum number of the bulblet produced in 1 mg/L PBZ but the explants treatment with the different concentration of PBZ did not show any significant effect on regeneration percentage. Ingeneral, The application of PBZ showed the higher number of the root formation compare to the combination of NAA with BA and using NAA in combination with BA produced the higest number bulblet compared to PBZ. Keywords : Lilium, tissue culture, NAA, BAP, PBZ