This paper presents a new method for the sensitivity analysis of membrane wrinkling based on the tension-field theory. This method can be applied to design membrane structures to reduce the occurrence of wrinkles. In this method, the wrinkle intensity in a partly wrinkled membrane is evaluated from an apparent strain energy resulting from the deformation through wrinkling. This wrinkle intensity is used as an objective function for wrinklereduction membrane design. Further, the sensitivity of the wrinkle intensity with respect to an arbitrary design parameter is derived by employing a semi-analytical differentiation technique and is used to resolve the minimization problem of the objective function. Some design examples show that this minimization problem can be effectively resolved by the proposed sensitivity analysis method and the occurrence of membrane wrinkles can be considerably reduced by minimizing the wrinkle intensity. Nomenclature a c = small constant value for the incremental line search B k L = strain-displacement relation matrix of the kth element b= design parameter vector b j = jth design parameter C = elasticity matrix for the membrane C m = modified elasticity matrix for the wrinkled membrane E = Young's modulus K = tangent stiffness matrix in the equilibrium state n 1 , n 2 = vectors for coordinate transformation of stress P, Q = projection matrices q = internal force vector in the equilibrium state r = penalty coefficient for the area constraint S = membrane area S 0 = initial membrane area s = step variable for the incremental line search s 1 , s 2 = vectors for coordinate transformation of the strain U s = penalty function for the area constraint U w = total wrinkle intensity over the entire membrane U k w = wrinkle intensity over the kth membrane element w k = weight coefficient for U k w = minute perturbation for numerical differentiation = minimum value of the ratio of the required membrane area to S 0 b j = numerical perturbation of b j U w = numerical perturbation of U w " = strain vector in the plane stress state " e = elastic strain vector " w = wrinkle-mode deformation vector " x , " y , xy = strain components in the x-y coordinate system " 1 , " 2 = major and minor principal strains, respectively " 2w = nonzero scalar value contained in " w = rotation angle of principal axes of stress and strain tensors to the x-y axes = Poisson's ratio = stress vector in the plane stress state t = uniaxial tensile stress vector in the wrinkled membrane x , y , xy = stress components in the x-y coordinate system 1 , 2 = major and minor principal stresses, respectively e = strain energy density in a wrinkled membrane p = strain energy density in a taut membrane w = wrinkle intensity at a material point ' = augmented objective function for shape optimization