This paper investigates the effects of corporate tax reform in Japan, wherein the (effective) corporate income tax rate decreases from 34.62% to 29.74% and the rates of size-based business taxation (levy on the sum of labor cost and other factor payment) rise at 2.5 times. We implement a simulation based on a dynamic macroeconomic model including capital structure (i.e., choices of equity, debt, and retained earnings) in the proposed model in order to implement investment, and measure the incidence of corporate income tax on labor income. This tax reform implies that the tax base is shifted from corporate income to labor cost, because it accounts for the majority of factor payments for most firms on which the size-based business taxation or "pro-forma" taxation is imposed. We find that the benefit on labor income from reduction of corporate income taxation is decreased by about 30% by expansion of the size-based business taxation from a simulation result. A reason behind the phenomena is distortion stemming from the size-based business taxation. Labor income increases due to lowering (effective) corporate income tax rate, nevertheless it loses due to rising rates of size-based business taxation.