Since 2000 there was a downward trend in defense spending throughout the world, but in Southeast Asia, overall defense spending experienced an increasing trend. The purpose of this study is to look at the level of militarism of a country with a natural balance of power approach, in which the indicators of the economy included in the calculation. The method used is descriptive method by analyzing the index level of militarization by GMI (Global Military Index) with the main indicator is the ratio of the number of soldiers, the ratio of the military budget, population and national income (GDP). The research shows that the absolute level of militarization of the ASEAN countries are high (except for Indonesia which is very low) but it has a tendency to decrease. This should be awared, because it can be a potential threat due to an unbalanced force between countries. With this awareness, ASEAN countries can cooperate with each other and remind each other as friends, as well as defense programs can be designed to maintain the growth of the national economy and peace in the region.