The aim of this study is to explore the effects of the pulsed electrical stimulation (PES) on the morphology, the proliferation and the values of NO and ET-1 of the endothelial cells (ECs). We chose the different frequency PES (1, 5, 10, 20, 50, 100 Hz) with 25 mV to stimulate the ECs for 6 hours. We observed the cell's morphous by the scanning electron microscope (SEM) and detected the values of MTT, NO and ET-1. The proliferation of the ECs was obviously rose up under the PES from 10 to 100 Hz. But the PES inhibited the proliferation with the frequency lower than 10 Hz. After stimulated with PES (20 - 100 Hz), the NO expression of ECs were increased obviously, and the peak value was appeared at 50 Hz. The peak value of ET-1 was appeared at 100 Hz. The PES has significant effects on the ECs' morphology, proliferation and expression of NO and ET-1. Particularly, the 50 Hz PES plays a positive role to enhance the ECs' function and to maintain the vascular biology.