Energy shortage has become the greatest bottle-neck arresting the development of economy.On the basis of an analysis of the energy intensity,changes of the energy intensity and the effect of change of the industrial structure on the energy intensity in Shanghai were studied in this paper.It was concluded that the development of industrial structure and increasing efficiency of energy utilization were two major factors which impelled the energy intensity to decrease.The decrease of energy intensity for the secondary industry predominantly led the fall of whole energy intensity,while the development of the tertiary industry increased the energy intensity continuously.Finally,some suggestions for decreasing the energy intensity were offered.