Abstract: The increase of distributed generators and the input of sensitive loads in microgrids have made it difficult to guarantee the system dynamic performance by relying solely on traditional distributed secondary frequency regulation strategy with progressive convergence characteristics, while the convergence upper bound of commonly used finite-time frequency regulation strategy is limited by system initial state and system parameters to varying degrees. To solve this problem, a distributed finite-time frequency regulation strategy with time-varying gain is proposed and designed based on the distributed control principle. First, the working mechanism of the traditional distributed secondary frequency regulation strategy is introduced, and the limitations of commonly used finite-time frequency regulation strategy are analyzed by using Lyapunov stability theory. Then, on the basis of traditional distributed frequency regulation strategy, the constant gain is improved to a time-varying function with periodic acceleration convergence characteristics according to its progressive convergence characteristics. And a distributed finite-time frequency regulation strategy with time-varying gain is proposed and designed, which solves the problem that the convergence time is limited by system initial state and system parameters. Finally, the effectiveness and superiority of the proposed method in accelerating frequency convergence and improving system flexibility are verified through the theory and simulation.