In order to satisfy the demand of flight simulation training and establish a realistic visual simulation environment, it is necessary to make image mosaic and fusion to multi-channel projection.Most of the existing technologies depend on the hardware support of the projector itself.In order to lower the requirement to the hardware environment, we studied the existing mosaic algorithms and made some improvements.A more reasonable and efficient method was used to accomplish curved-surface generation and projection transformation to the images produced by scene rendering module, thus to make the image projected onto the spherical screen through the projector be a normal image.Then, transition processing was made from bright to dark to the brightness of overlapped part of the images from several projectors, to make sure of the smooth transition of images of different projectors.The verification result showed that, the image processed by the mosaicing and fusion system can achieve a seamless display effect of multi-channel projection on the spherical screen, which achieves the expected qualification.