In this paper we discuss an optimum taxation system. The idea for this we use supply function and demand one for surplus analysis. By taxation each surplus is reduced some what, we maximize the total surplus for all markets, under the condition of the required tax amount. D_i(x_i)/D_i(x_i^*)-S_i(x_i)/S_i(x_i^*)=λ (∀i: Market) Demand function D_i(・), supply function S_i(・), equilibrium quantity x_i^*.
