The application provides a method for partitioning a watermark image with western language characters, comprising: partitioning a western language characters image along rows and columns to form a plurality of character image blocks; identifying valid character image blocks from the formed character image blocks; counting sizes of the valid character image blocks to determine if the image corresponds to a document with a large font size or a document with a small font size; dividing words in the image into a plurality of groups, wherein each divided group in the document with large font size has different numbers of words from that with small font size; and dividing equally the divided word groups into multiple portions corresponding to watermark image blocks. The application further provides a device for partitioning a watermark image with western language characters. The operability of watermark embedding process can be ensured through the above technical solution.