A system and method relating to image processing are provided. The method may include the following operations. First data at a first bed position and second data at a second bed position may be received. The first bed position and the second bed position may have an overlapping region. A first image and a second image may be reconstructed based on the first data and the second data, respectively. Third data and fourth data corresponding to the overlapping region may be extracted from the first data and the second data, respectively. Merged data may be generated by merging the third data and the fourth data. A third image may be reconstructed based on the merged data. A fourth image may be generated through image composition based on the first image, the second image, and the third image.