An X-ray imaging system with multiple pulsed X-ray source tubes in motion to perform highly efficient and ultrafast 3D radiography is presented. There are multiple X-ray tubes from pulsed sources mounted on a structure in motion to form an array of X-ray tubes. The tubes move simultaneously relative to an object on a pre-defined arc track at a constant speed as a group. Each individual X-ray tube in each individual source can also move rapidly around its static position in a small distance. When a tube has a speed that is equal to group speed but with opposite moving direction, the tube and X-ray flat panel detector are activated through an external exposure control unit so that the tube stay momentarily standstill. It results in much reduced travel distance for each X-ray source tube and much lighter load for motion system. 3D X-ray scan can cover much wider sweeping angle in much shorter time and image analysis can also be done in real time.