Being an advance technique, the imaging fusion is applied in biology cell images processing. The resultant merged image would contain more information than any of the individual image. It can match the images and improve the confidence of images and spatial resolution. In this article, a simple pixel based algorithm is applied to combine the fluorescence image and transmission image into a single composite image with extended information content. The method is also benefit to correctly judge the position of fluorescence and analysis of biological mechanism of fluorescence.