The word "Hikikomori" was originated from Japan to describe a group of people who live in seclusion at home， away from their families， friends， not to go to school， not to work， and not to be employed. In recent years， other countries have also seen cases of "Hikikomori". This article reviews the related research from the perspective of the diagnosis， incidence， assessment tools， related factors， and intervention methods of "Hikikomori"， and puts forward the key points for future research.