In this paper, an effective data hiding method for encrypted JPEG 2000 codestreams is proposed. By using the property of the discrete wavelet transformation (DWT), an image is visually encrypted: multiplying random signs to the discrete wavelet transformed (DWTed) coefficients of the image, where the image is also compressed in the DWTed domain by JPEG 2000. In addition, data hiding is performed in the DWTed domain as well. It provides a number of possible applications; the hidden data may be extracted and then the original image is recovered, or the codestreams is directly decoded and decrypted to get the image containing the hidden data. Experimental results show that the proposed method is efficient in terms of visual protection, quality of decrypted images containing the hidden data, and hidden data extraction.