The economic policy includes a set of policies that are homogeneous each of them to achieve the general objectives of the state such as fiscal policy, monetary policy, exchange rate policy and trade policy. The research problem revolves around identifying the reality of fiscal policy in Japan, and its contribution to the GDP in Japan through analyzing the data for the study period 1981, 2015. Results indicated that Japan achieved the highest average in the value of public revenue in the period from 2001, 2015. The results of the standard analysis of the data also revealed that public spending is the most important determinant of increasing the size of the gross domestic product in Japan. The research recommends using of a fiscal policy by activating the public spending tool for use in building an infrastructure that works to increase the volume of investment and from it to positively affect growth rates.