Abstract: Both advantages and disadvantages of CCD camera and scanner used as image acquisition equipment for leaf area measurement using image processing methods were discussed in this paper.For the main limitation of currently used leaf area measuring methods,which was that only one piece of leaf could be measured separately,a novel algorithm based on MATLAB was figured out to measure each leaf area synchronously in a multi-leaf scanned image.Results of experiments were as follows: the accuracy of leaf identification when no superposition between leaves was 100%,the relative error of calculated leaf area between using this method and weighing method was 2.43%,the determination coefficient R2 was 0.999 6.Results indicated that this method can be used in the object identification and leaf area calculation in a multi-leaf scanned image.