Abstract: As an emerging Rapid Prototyping Technology, 3D printing has been widely used in the fields of archaeology, automobile, mold making, etc. It has gradually changed the current production pattern characterized by standardization and large-scale production. CT, as an increasingly developed technology, has been one of the most important imaging methods in clinical medicine and industrial non-destructive testing. 3D printing and CT technology can be combined as a whole solution to realize scanning, digitalizing and editing the entity objects, creating the precise copy and redesigning due to their complementary functions. Their combination can solve many problems such as rapid production of the medical implants, prostheses and surgical guides which match the individual body characteristics, showing the wonderful prospects in the fields of clinical medicine, reverse engineering, equipment testing and maintenance, etc. The paper firstly introduces the 3D printing technology, and analyzes the flow chart of the combination of 3D printing and CT technology, then focuses on the key technologies in the procedure. Finally, the existing drawbacks of such technical combination and the future development are summarized based on the current typical applications.