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Digital watermarking,as a name of a new information hiding technology proposed at the end of the 20 th century,can embed some specific digital signals such as text,image,video,or audio files into digital products to protect the copyright,integrity,anti-duplication or destination tracking of digital products.It was developed recently as a new method for copyright protection problems.This is a technique to insert into digital carrier some authentication data,which could be hardly either to detect or to erase.The carrier can hide some secret information without being found by readers or detectors.This hiding technology is also called invisible watermarking technology.The research content of this dissertation will focus on embedding Mongolian characters into images as invisible watermarks.The main pretreatment method will be Discrete Wavelet transform（DWT）.During the last three decades,many digital watermarking schemes based on methods in space domains（or spatial domains）or transform domains（or frequency domains）were proposed.Spatial domain methods still have the most relatively low-bit capacity in the industry.Frequency domain-based methods are proved with better robustness and lager capacity.Some frequently-used treatment methods in watermarking based on frequency domain includes: Discrete Cosine Transform（DCT）,Discrete Wavelet Transform（DWT）.In this dissertation,one novel digital watermarking method including embedding and extraction oriented to copyright protection based on DWT is proposed.The most innovative thing in this algorithm is choosing the Mongolia character as the secret data.As for Mongolia,digital watermarking yet developed its full capacity.This thesis could be the beginning of usage of digital watermark in every sector in Mongolia in near future.This method will be implemented using MATLAB and their effectiveness and ability to recover the authentication information after some distortions of the images will be verified.