As medical imaging applications become more complex, the design of software platforms for medical imaging is getting greater priority. With this demand, we have designed and implemented a novel software platform for medical data visualization in traditional object-oriented fashion with some common design patterns. This platform integrates the mainstream medical data reconstruction and visualization algorithms and 3D human-computer interaction based on 3D widgets into a consistent framework. The design goals, the overall framework and the implementation of some key technologies are addressed in details, and some application examples are also given to demonstrate the abilities of this platform. The ultimate objective is to provide a flexible, reliable and extensible 3D medical data visualization platform for the medical imaging society.