The invention discloses an urban energy internet operation and energy storage capacity optimization method, which comprises the steps of S1, constructing an operation and energy storage configurationoptimization model for the operation and energy storage capacity optimization problem of the energy internet; S2, proposing an improved co-evolutionary algorithm for the operation and optimization configuration problem; and S3, solving the operation and energy storage configuration optimization model by adopting the improved co-evolutionary algorithm to obtain an optimal operation optimization result and optimal energy storage capacity configuration. The method adopts a particle swarm algorithm as a basic algorithm of the improved co-evolutionary algorithm, and couples strategy collaboration and double-population collaboration; the strategy collaboration is composed of an average entropy initialization strategy, a Tent chaos initialization strategy and an adaptive weight strategy, and thedouble-population strategy is composed of different strategies adopted by different populations. According to the invention, the urban energy internet operation and energy storage capacity optimization model is solved, the system optimization is achieved, efficient energy supply of an urban energy internet system is guaranteed, and the energy utilization rate is improved.