The invention relates to the technical field of data sharing, and discloses a data sharing method of a cloud computing system, which comprises account registration, identity information authentication, data input management, data classification, data output management and data arrival at a user side. According to the invention, people's opinion to resource sharing can be changed; corresponding rewards are given to the sharing of the valuable data; an individual and a company have a support attitude for resource sharing, the sharing mode can effectively protect the safety of data information, the problem of data leakage in the transmission sharing process is avoided, and meanwhile, the quick check and retrieval of resource data by a user side can be effectively improved.