。When a doubled crystal is placed within a multimode solid-state laser cavity,large amplitude fluctuations (the noise of the intracavity-frequency-doubled solid-state lasers ) are observed.Through numerical simulation of coupled differential equations which describe the noise dynamics of the intracavity-frequency-doubled laser found that the losses of fundamental longitudinal modes effect the properties of noise when two or three fundamental-frequency longitudinal modes are operated.. The periods of power fluctuations of intracavity-frequency-doubled laser are decreased and the numbers of peaks are increased if the losses are larger. Through FFT translation of power fluctuations of frequency-doubled laser, the noise will distribute at larger frequency regions and the frequency-spectrum of noise will remove to high-frequency regions.