This study presents about the method of alternatives selection by considering wall performance and interior design. Wall is selected fur the object and 3 items of cost, performance, and design as the objective function for optimizing are determined. Thus the wall performance selected problems, which are improvement of insulation performance, sweaty prevention, sound insulation performance and design selected problems, which is satisfactory Improvement of users about Interior design. It is important to select alternatives that can satisfy the performance and design on the capital given as much as possible. But quantitative problem such as performance or expanses and qualitative problem such as design are not in the same dimension. Therefore this problem is a multi-criteria optimization problem and also has used AHP method as the method to solve these. Moreover GA is used to solve a problem of the alternatives occurrence, which is the characteristic of multi-criteria problem. This study presents the solution method on multi-criteria problem that has been mix loaded of quantitative problem and qualitative problem by using AHP(Analytic Hierarchy Process) and GA(Genetic Algorithm).