Abstract: A discharge-pumped 351 nm XeF(B-X) excimer laser has been developed. For improving output efficiency and energy and achieving stationary discharge, the laser adopted a new switching power supply, compact Chang’s electrodes and spark preionization structure, and the optimization of storage/discharge capacitances and working gas mixture was performed. The maximum laser efficiency of the laser is 0.88%. When the laser works at 30 kV with the maximum repetition rate of 80 Hz, the output energy is about 153 mJ/pulse, the average power is 12.9 W, the pulse-to-pulse energy stability is no more than 4%, and the beam dimensions are 7 mm×22 mm near the output window. The laser has been applied to the experiments of the printed circuit board(PCB) lithography system based on resist exposure.