Virtual Power Plant integrated large numbers of distributed generations, energy storage devices and loads into a controllable independent power plant by advanced communication technologies and control strategies. It can solve the control and dispatch problems of distributed generations connecting to network effectively by a series of large-scale means. In this paper, we made a comprehensive review on virtual power plant from the aspects of information exchange architectures, operation and management structures, ancillary services and optimal scheduling respectively as well as explored the energy management optimization scheduling problems of virtual power plant deeply. For the optimal scheduling problems, we analyzed in detail mainly from three aspects of optimization goals, scheduling periods and the uncertainties in virtual power plant. Finally, some suggestions are given for further studies of virtual power plant on organizational structure, scheduling management, operational control and so on, so as to form a practical theoretical framework.