Abstract: Power source of magnetron sputtering coating is one of the key equipment in magnetron sputtering system. A power supply of magnetron sputtering with adjustable output voltage of 0-800 V, pulse width of 5-200 μs, frequency of 0-60 Hz and maximum pulse current of 150 A is developed according to the technical parameters of the sputtering treatment equipment for niobium and tin targets. The experimental results of the prepared power supply with the niobium target load and tin target load are given respectively. To solve the problems of unsuccessful sputtering of particles, inconsistent ionization time, poisoning of target surface and low sputtering efficiency in high power magnetron sputtering under repetitive frequency operation, a high power bipolar pulse forming circuit integrated with high voltage short pulse preionization is adopted. The gas pressure can realize sputtering coating with low pressure. This design has improved the sputtering efficiency of the target and reduced the surface roughness of the film. The results of experiments show that the prepared power supply achieves the ideal sputtering effect and meets the requirements of the index.