The invention provides a fast fusion system and an implementing method for remote sensing images. The fusion system comprises an image preprocessing module, an image IHS (Intensity, Hue, Saturation) parallel fusion module, an image PCA (Principal Component Analysis) parallel fusion module, an image wavelet parallel fusion module and an image fusion effect parallel evaluation module. Both the image preprocessing module and the image fusion effect parallel evaluation module are connected with the image IHS parallel fusion module, the image PCA parallel fusion module and the image wavelet parallel fusion module. According to the fusion method, parallel fusion and evaluation are adopted. The invention provides the simple, convenient and efficient fast fusion implementing method for the remote sensing images, provides the efficient fast fusion method and implementing system for the remote sensing images for the remote sensing application in the fields of disaster prevention and relief, military and the like, and solves the problem of low fusion speed of the remote sensing images with large data volumes.