STEP-NC provides a way for intelligent NC manufacturing and seamless connection of the computer systems in design and manufacturing industries. It also makes it a must for a new breed of CNC machines to interface directly with the new part programs in STEP format (ISO 10303-21). In this paper, the data model and structure of part programs based on STEP-NC (STEP AP 238) are overviewed. Available tools are discussed and a method of extracting the manufacturing information from STEP-NC physical files is presented, and corresponding software module are developed in ST-DeveloperTM environment. With the aid of the STIXTM and ROSETM C++ library, the general information, feature information, technological information are extracted from the STEP-NC file and organized in a tree structure according to the hierarchy of the data model, which is essential to further usage of the manufacturing data, such as process planning, tool-path generating etc.