knowledge reuse and standard parts library. Knowledge reuse is a similarity relation fundamentally. Knowledge reuse technology mainly includes CBR (Case-Based Reasoning), KBE (Knowledge Based Engineering) and ANN (Artificial Neural Network). CBR is a typical form of design reuse technology, consists of retrieval, reuse, revise and conservation, which is widely used at present [7-8]. Standard parts library is an important part of CAD technology. Need to solve the following problems while applying knowledge reuse to standard parts library: 1.creating standard parts models; 2.expressing standard parts knowledge; 3. knowledge reuse of standard parts; 4.inquiry knowledge in standard parts library; 5.editing standard parts; 6. quick assembly of standard parts; 7.searching for standard parts [9-10]. Although the present CAD platforms have studied and developed corresponding standard parts library, they didn’t support the whole process in mechanical product design (e.g. demand analysis, concept design and detailed design). NX system develops a practical KBE technique, which can not only realize the automatic design of product structure based on knowledge reuse, but also accumulate design experience of enterprises. Applying development tools provided by NX software to redevelopment is convenient to embedding enterprise knowledge and standard into NX platform, establish own parts standard system and improve the reusability of components. The management and application of NX reuse library. Reuse is a flexible way to add or register a reusable object in the assembly. The standard parts libraries of NX are integrated into a reusable component library, so as to manage standard parts in a more effective and flexible method. In mould design process, we can use reuse library based on NX to realize the rapid development and innovative design of product. Aiming at the case of knowledge reuse and injection mould design in this paper, we need to customize user-defined standard components in the reuse library. The following describes the way of adding standard parts based on NX injection mould design module. 1) Create content, register NX standard parts content to the library. 2) Register standard parts in the registration spreadsheet file. 3) Build template parts of standard parts by using NX parametric modeling function. 4) Make standard bitmap file. 5) Establish standard parts database. 6) Apply, verify and debug standard parts. The result is shown as Fig.1.