Four kinds pf cavity configurations of dye lasers transversely pumped by high PEF CuBr lasers are investigated and their operating characteristics compared. The doable prism expander with Littrow mounted grating cavity is found to be the optimum. Linewidth achieved is 0.0012 nm in 598~640 nm range and the conversion efficiency is 7.5%. The amplified: spontaneous emission of 1.5% and single longitudinal mode operation areobtained.