System in package(SIP)is characterized by any combination of more than one active electronic component of different functionality plus optionally passives and other devices like MEMS or optical compo- nents assembled preferred into a single standard package that provides multiple functions associated with a system or sub-system. It uses mature sealing process to integrate many kinds of primary devices with system on chip(SOC)supplementary to realize the hybrid integration. SIP futures design flexible, short cycle and low cost. This article describes development and the superiority SIP, and to discuss the SIP product structure. And also the correlation technology and the future prospects are given.