Transparency and stability are two key issues in bilateral teleoperation. In this paper, We propose a novel control framework for bilateral teleoperation of nonlinear robotic teleoperation systems under constant communication delays. The proposed approach utilizes the modified wave variable method based on the adaptive nonlinear control, the master and slave robots are directly connected over the delayed communication channels. To make the stability of the system independent of the communication delay, two nonlinear adaptive motion/force controllers are bilaterally designed for both master and slave manipulators and insured its passivity. To improve the transparency, a modified wave variable method based on Nimeyer-Slotine wave ways was used. Simulation results are presented which demonstrate the effectiveness of the proposed architecture.