We developed an information processing system that optimizes material compositions using an annealing method based on the Ising modelIsing model. The system includes a computing device that executes annealing calculations and a material composition search device that converts the optimizationOptimizations function into an Ising modelIsing model. Critical components of the system are the Input Unit, which accepts target values for physical properties; the Conversion Unit, which converts the optimizationOptimizations equation into the Ising modelIsing model; the OptimizationOptimizations Unit, which calculates the optimal material composition approximating the target values; and the Output Unit, which outputs the calculated optimal material composition. The equation includes a cost function that calculates the cost of compositions to prioritize low-cost materials and constraints to ensure the total ratio of materials sums to 100% and to favor compositions with fewer materials. We applied this system to search the mixture solvent to maximize the solubility and minimize the cost.