The purpose of this study is to analyze the possible relationship between industrial structure and economic development in rural areas in South Korea. Accordingly, this study uses the Herfindahl–Hirschman Index and a two-step cluster analysis method to conduct an empirical analysis of the rural areas of Chungcheongbuk-do as the research object. The results show that among the 11 regions with concentrated industrial structures, the cluster results of 2 regions changed from the decentralized low employment cluster in 2010 to a concentrated high employment cluster in 2015, while the cluster results of other regions remained unchanged. Among the 18 regions with decentralized industrial structure, the cluster results of 5 regions changed from the concentrated high employment cluster in 2010 to the decentralized low employment cluster. Meanwhile, the cluster results of three regions changed from the decentralized low employment cluster in 2010 to the concentrated high employment cluster in 2015, while the cluster results of other regions remained unchanged. Based on this, it can be concluded that, for general rural areas, a low level of industrial diversification, that is, a concentrated industrial structure, is more conducive to promoting the economic development of rural areas. However, there is a special case, namely that rural areas with certain specific advantages, a high level of industrial diversification, or a decentralized industrial structure are more conducive to the development of the regional economy.