This invention provides a method and system for decrypting an optical disc. The contents of the optical disc are encrypted, and the decrypting information is stored in the Internet server. The decrypting information is created by the internet server in terms of the request, including two layers of data, the first layer contains the information related to the data of the optical disc which can not be copied, the second layer contains the encrypted method for decrypting the optical disc. When the optical disc player receives the decrypting information, firstly, it acquires the data from the optical disc to be played which can not be copied according to the information of the first layer, and then decrypts the data of the second layer using the data which can not be copied, thus to acquire the method for decrypting the optical disc and the related parameters.