Rapid developments in Information Technologies have eased data sharing through the Internet recently. Copying or modification of digital data without permission and sharing by unauthorized users have brought copyright protection problem. Even though cryptography can be used to share sensitive information securely, it cannot be used to protect copyright since encrypted information cannot be associated with the original. Digital watermarking methods are used lately in digital rights management. Methods to hide specially crafted secret information or watermark into digital media provide additional security mechanism in protecting the data and determining the ownership information. Algorithms recommended for right management in multimedia files cannot be applied directly on databases. Some methods used for watermarking databases take advantage of Extensible Markup Language (XML) data fields attached. A new method based on Homoglyph Transformation in XML fields is proposed in this manuscript. Primary key and hash algorithm are used together in the selection of lines to be watermarked in the database. Results indicate improved robustness against various attacks in high watermarking capacity by the proposed method compared to other methods reported in the literature.