Article 9 of the Japanese Constitution is a clause in the Constitution of Japan outlawing war as a means to settle international disputes involving the state. The Constitution came into effect on 3 May 1947 during the Allied occupation that lasted until 28 April 1952, following the surrender of Japan in World War II. In its text, the state formally renounces the sovereign right of belligerency and aims at an international peace based on justice and order. The article also states that, to accomplish these aims, armed forces with war potential will not be maintained. The Constitution was imposed by U.S. military occupation to prevent rearmament of Japan in the post–World War II period.

The Constitution of Japan is the constitution of Japan and the supreme law in the state. It was written primarily by American civilian officials working under the Allied occupation of Japan after World War II. The current Japanese constitution was promulgated as an amendment of the Meiji Constitution of 1890 on 3 November 1946 when it came into effect on 3 May 1947.