Lager amplitude fluctuations of output power at high-frequency are observed in laser-diode pumped intracavity frequency-doubled Nd:YAG/LBO blue laser of 473nm without special intracavity elements .This is called the “Blue problem” which seriously restrict the development and applications of the blue laser of 473nm in many fields . To suppression the high-frequency noise of frequency-doubled output of the blue laser

method of decrease reabsorption losses in quasi-three-level laser system through increase intracavity circulating intensity of fundamental wave and decrease length of laser crystal was used . Two LD of 2W as pumped source and a Nd:YAG crystal of 1.0mm length were used in experiment . Blue laser of output power at 195mW with low noise operation was obtained by intracavity doubling through LBO material of 10mm length . Experiment indicated that the (peak-peak)/mean value of frequency-doubled output power of the blue laser are lower than 1% . Not any hopping of output power of the laser are observed in 1h and not any intracavity elements to control state of longitudinal mode are introduced .