Cloud computing has been one of the most popular topics on information technology, since it was proposed by Google in 2007. In the past years, cloud computing has become from a theoretical concept into the real applications in different industries such as telecommunication and healthcare. Inevitably, its influences on different industries have also attracted much attention. Based on the literature review, this paper discussed how the traditional E-commerce businesses and industry were influenced by cloud computing in technical architecture, service modes and the industrial chain. Besides, it analyzed the driving-forces which led to the changes of E-commerce in cloud era. Finally, it concluded that only when the E-commerce enterprises involved cloud computing in the business strategy and established the core competencies, could they realize the sustainable development in the cloud era.