The invention discloses a high-proportion renewable energy power grid adaptability planning method based on joint weighted entropy. The method comprises the following steps: S1, establishing a power transmission network multi-objective planning model based on the adaptability index, the planning model taking a newly-built power transmission line as a variable and taking a total construction cost,a power grid state adaptability index and a power grid structure adaptability index as objective functions, and the constraint conditions including a power grid connectivity constraint, a newly-builtline return constraint and a power grid safe operation constraint; and S2, solving the power transmission network multi-target planning model by adopting a multi-target particle swarm algorithm in combination with a data envelope analysis method with an analytic hierarchy constraint cone to obtain an optimized planning scheme. The method is based on the uniformity theory and the entropy theory, considers the safety and stability of the actual state of the power grid and the balance and rationality of the electrical structure of the power grid in an uncertain operation environment, and is moresuitable for the multi-target planning of the power grid under the multi-dimensional attribute.