Background Sepsis is a severe illness caused by overwhelming infection of the bloodstream and a complex response involving many cell types and biological mediators. It causes 1400 death around the world each day approximately, affects more than 3 million people in China each year. There is more evidence on the mechanism that both neutrophils and platelets are actively involved in sepsis, and contribute to the inflammatory response cooperately. Objective This article reviews the research advance on roles of platelets in the development and processing of sepsis,especially its activation on neutrophils．Content This paper describes some of the mechanisms of cooperativity between platelets and the immune system in sepsis, and also the novel pathway for bacterial trapping in the vasculature. Trend The further insights into its detailed mechanisms may provide a nice prospect for the therapy of sepsis．