Abstract: In this review I present an introduction to and a summary of high power particle beams (HPPB) and their applications.I take Flash-I Intense Pulsed Electron Beam Accelerator for example to describe the essential machine technology,principle of operation and their performance.HPPB have been successfully used for several important research areas:prompt gamma simulator,flash x-ray radiography,high power laser studies,inertial confinement fusion,generation of high power microwave,collective acceleration of ions.et al.This paper also briefly describes the progress in accelerator constructions and applications in China.Finally,related topics of future development are also given.