A dye laser with: a double-prism pf one dimensional beam-expander, which is longitudinally pumped by a frequency doubled Nd: YAG laser, is reported. The total efficiency of the dye laser after two stages of amplification is 31% for Rh6G. Then the energy of pumping beam was 40 mJ, tunable dye laser output of 12.2mJ (2MW) Tith a line width of 0.12A was obtained. The quality of laser output beam was good. The repetition was 10Hz when a circulating system was used.