Abstract: High-performance electromagnetic transient (EMT) simulation is a necessary analysis tool for the safe operation of new-type power systems. Due to the limitation of modeling and simulation ability, computational efficiency, and scalability, traditional EMT simulation tools are difficult to adapt to the needs of new power systems. To this end, this paper solved the problems of considerable difficulty in modeling and simulating large-scale new-type power systems, high cost of improving simulation efficiency and poor ability to support decision-making of the existing EMT simulation platforms through the innovation of new-type power system EMT modeling, high-performance parallel computing and scalable EMT simulation platform construction. A cloud computing-based EMT simulation platform for new-type power system was developed, forming a shared and flexible simulation system.