The invention discloses a large-scale wind power access power grid multi-objective optimization method considering the elasticity of a power transmission plan and aims to provide a theoretical basis for promoting wind power consumption. According to the method, comprises the following steps: a large-scale wind power access power grid multi-objective optimization model is constructed with a maximumwind power delivery quantity and minimum system operation cost adopted as objective functions and a medium-and-long-term power transmission plan elastic space adopted as a constraint condition, so that a multi-objective problem is converted into a single-objective problem taking a maximum satisfaction degree as an objective; and the model is solved by adopting an improved particle swarm algorithm; and therefore, the large-scale wind power access power grid multi-objective optimization method considering the elasticity of the power transmission plan under a medium-and-long-term time scale is realized.