In order to contribute to security sharing and transmission of medical images, this paper propose a new approach for Watermarking image based on the techniques of Code Division Multiple Access (CDMA), Discrete Wavelet transform (DWT) and Error Correcting Code (ECC). The motivation of this approach is to improve the quantity of data integration with the conservation of the image visual quality. Therefore, this work permits to the user the capacity to correct the possible alterations if it exists. IRM and Echographic medical image are used to experiment this approach.