By adopting the gain-noise model of the single-mode laser in which the pump noise is subject to amplitude modulation wave and the action of biased signal, we use the linear approximation to calculate the power spectrum and signal-to-noise ratio (SNR) of the laser intensity, which is driven by two colour noises correlated in the form of an exponential function. The result shows that the SNR shows stochastic resonance with the variation of the noise intensity, the self-correlation time of the pump noise, the parameter of the laser system, the carrier frequency and the signal frequency of the amplitude modulation wave.