Laser oscillation was observed from Xanthine dye solutions pumped with the second harmonics light of a Q-switched ruby laser. These Xanthine dyes were rhodamine 6G, rhodamine B, rhodamine S and rhodamine F3B. Three kinds of solvent, ethanol, acetone and ethylene-glycocl were used. The spectral range of laser oscillation obtained from the combination of these dyes and solvents was about 570 nm-640 nm. Further in each dye solution, the laser spectral range had it's width of about 20 nm. As for the solvents, the ethylene-glycol had the laser oscillation having the longest wave length. On the laser oscillating characteristics when two kinds of dye solution were mixed, it was proved apparent that the laser oscillation depended on only one having the lower energy level of spectral characteristics.