Flash radiographic accelerators with high energy pulsed X-ray have important applications in hydrodynamic experiments, which is recognized as an important motivation to drive the development of the pulsed power technology. This paper reviews the advantages, typical facilities, and technical weaknesses of three kinds of flash X-ray radiographic accelerators, including the radio frequency linac, electron induction accelerator, and high-current accelerators driven by the high-voltage pulsed-power source and diodes. The technology trends for the future are summarized, as follows: (1) to develop accelerators capable of producing co-axial multi-pulse X-ray; (2) to develop compact, small and mobile accelerators by employing all-solid-state pulse power components.