Chickenpox is an acute and highly infectious respiratory disease commonly seen in children.Varicela－zoster often results from the activation of latent virus in chickenpox called varicella－zoster virus（VZV）or called human herpesvirus type 3. Primary infection of VZV may induce typical disease of various severity and most healthy children infected with VZV have mild symptoms and good prognosis.But VZV infection，if occurs in special population such as persons of immune inhibition treatment will induce serious consequence or even death and it is as same serious as in adults.A detailed illustration of molecular biology，epidemiology，laboratory diagnosis，treatment and preventive strategy of the VZV were given.