Digital watermarking is the technology of embedding information (i.e., watermark or host image) into the multimedia data (such as image, audio, video, and text), called cover image. It is realized by embedding data that is invisible to the human visual system into a host image. Watermarking techniques have been used in multimodal biometric systems for the purpose of protecting and authenticating biometric data and enhancing accuracy of identification. A multimodal biometric system combines two or more biometric data recognition results such as a combination of a subject's fingerprint, iris and palmprint. This increases the reliability of personal identification system that discriminates between an authorized person and a fraudulent person.