ChangJiang Electrouic Navigational Chart(CJENC) covers a variety of elements and attributes which are essential and important information to guide safe vessel navigation. But according to related confidentiality laws and regulations, some of the elements and attributes belong to confidential content and can’t publish externally.In order to ensure normalization and security of the data, based on a comprehensive analysis of related confidentiality laws, regulations, waterway elements and attributes, this paper probes into the security classification and decryption processing method about waterway elements of CJENC. It can ensure that the CJENC guides safe navigation of vessels. Meanwhile, the security of data publishment is guaranteed.