Abstract: The accelerated integration of traditional power systems with other energy systems leads to a new ecology of energy interconnection. In the Energy Internet, the separation of data usage rights and data ownership, and the separation of information resources and computation resources make the privacy preservation problem of multi-party collaborative optimization increasingly prominent. Starting from the analysis of typical modes for collaborative optimization of Energy Internet, this paper summarizes the privacy risks of the traditional agent computation mode with a third party, and interactive computation mode without any third party. Preliminary technical schemes for mechanism collaborative optimization of Energy Internet considering privacy preservation are proposed. First, a secure agent computation scheme based on information masking is proposed for the scenarios with a third party. In this scheme, the characteristics of information masking algorithms, the construction method for operators and its application scenarios at the user level, cluster level and system level based on cloud services are studied. Then, a secure multiparty interactive computation scheme based on secret sharing principle is proposed for the scenarios without any third party.Combined with the multi-centric and fully distributed application architectures, the differences in characteristics of this scheme when applied to the scenarios with a large number of clients or a small number of clients are analyzed. The proposed schemes protect the rights and interests of data owners from the perspective of data privacy and computation security, reduce the risk of data disclosure in collaborative optimization computation of Energy Internet, and finally achieve reliable privacy preservation.