As research on the applications of high-precision membrane structures develops, wrinkling has become a popular topic. Here, we present a new wrinkle-wave model to describe wrinkles more accurately. First, the characteristics of wrinkle-waves that result from radial tension stress applied at the vertex of a triangular structure were analyzed. However, for polygonal structures under more than two tensions, the influence of the other vertexes should also be considered. Therefore, by introducing a load ratio, we constructed a wrinkle-wave model of a square membrane structure subjected to corner forces. This model is applicable to various loading cases and polygonal membrane structures. Comparison among the results of the finite element analysis, and the experimental and analytical results showed that the proposed model more accurately described the wrinkling details and solved the problem of convergence that is encountered during finite element analysis.