This paper is a attempt to accurately assess 1950s` Korean Economy. For this, this paper focuses on grant-in aid, America`s policy intervention on Korean Economy and Rhee`s economic policy. Grant-in aid that served to relieve imbalance in physical and fiscal areas was very important resources in reconstruction of Korean Economy. But it was accompanied by America`s policy intervention. Aid has an effect on Korean economy through three areas: what goods, reserve and use of counterpart fund. In fact, Korean Government and U. S. Government that oriented different reconstruction target conflicts with each other in all this parts. Therefore, we take account of these points in assessing 1950s` Korean Economy.