The imaging mechanism of ghost imaging determines that it needs a large number of measurement, measuring the more the better imaging quality, but the longer imaging time. Therefore, multi-wavelength ghost imaging system is proposed, it can reduce imaging time through changing system composition, since different detectors measure different wavelength intensities simultaneously. Experimental results indicate that when light source with three wavelengths is used to imaging the target at the same time, the contrast ratio improves by 36% and the carrier noise ratio improves by 66% , comparing with conventional ghost imaging system with single wavelength.