In view of the problems of the product digital design in the small and medium-sized cutter manufacturers, the information integration model of the digital design platform was established based on the STEP-NC standard. The systems were integrated into the platform according to the architecture of SOA. The structure of the platform was divided into 3 layers: the data layer, the application layer and the user layer. The key technologies of the platform were put forward, including the geometric modeling technology, the collaborative design technology, AP224 file conversion technology, 3C integration technology, etc. Based on these, the integration platform of cutter digital design for small and medium-sized enterprises was developed. The development environment and implementation methods of the platform were proposed. The platform has been applied to the enterprise and run well.