This study attempts to measure economic knowledge of Korean primary school teachers in the Inchon and Kyonggi region, and analyze what they understand well and do not understand well. This study also compares the economic literacy of Korean primary school teachers with that of high school students of U.S., U.K., Australia, and Korea. Finally, the key elements affecting economic knowledge of Korean primary school teachers are estimated. For these purposes, 239 primary school teachers are examined. The sample consists of 207 female and 29 male teachers, and 3 teachers are not answered. They are 28.7 years old, and have 4.3 years of teaching experience on average. The test material used is TEL(Test of Economic Literacy) developed by Soper and Walstad in 1987. The test result shows that their average score is 31.2, with perfect score of 46. The highest score, the lowest score, and the standard deviation are 42, 14, and 4.6, respectively. The average score of Korean primary school teachers is higher than those of high school students of U.S., U.K., Australia, and Korea by 1.1-9.8. The economic concepts that primary school teachers do not understand well are nonexclusive public goods, free trade, competitive market, interpreting graphs, aggregate demand and supply, fiscal policies, monetary policies, profit, the role of trade union, and the exchange rate. The study suggests that Korean primary school teachers need more economic knowledge to raise the effectiveness of economic education for primary school students. Reinforcing economic education for pre-service teachers in the university of education, and enlarging training opportunities on economics for in-service teachers are strongly recommended.