The “Miracle on River Han”, according to conventional wisdom, was made possible by the government’s strong interventionist economic policies. Many books and papers which attempted to explain the miracle paid little attention to the large world market, the important reason of the miracle. This paper examines how the rapid export expansion started in the early 1960s and the effects of Export Promotion policy. Also, it finds the Heavy and Chemical Industry policy was the reason behind the negative economic growth in 1980. It claims that the ‘industrial upgrading’ was largely the result of very rapid capital accumulation and the consequential shift in the economy’s comparative advantage in the world market.