Dissipative particle dynamics (DPD) is a mesoscale particle method that bridges the gap between microscopic and macroscopic simulations.It can be regarded as a coarse-grained molecular dynamics (MD) method suitable for larger time and length scales.It has been successfully applied to different areas of interests, especially in modeling the hydrodynamic behavior of complex fluids in mesoscale.This talk presents an overview on DPD including the methodology, fbrmulation, implementation procedure and some related numerical aspects.The paper also reviews the major applications of the DPD method, especially in modeling 1) micro drop dynamics, 2) multiphase flows in micro channels and fracture networks, 3) movement and suspension of macromolecules in micro channels and 4) movement and deformation of single cells.