Lithological and petrochemical characteristics and tectonic setting of the Cretaceous volcanic rocks in Hampyeong area located in the southwestern part of Okchon Zone, were studied by field survey and petrochemistry of major, trace, and rare earth elements. The $SiO_2$contents of the volcanic rocks range from 50.8 to 77.2wt.%. With increasing $SiO_2$, $Al_2O_3$, $Fe_2O_3;^T$, $TiO_2$, MnO, CaO and MgO contents decrease and $K_2O$content increase, but $Na_2O$content is scatter to the trend. According to TAS and AFM diagrams, the Cretaceous volcanic rocks are calc-alkaline series. On the discrimination diagram of $K_2O$versus $SiO_2$, the volcanic rocks belong to high-K rocks series. The trace element compositions and REE patterns of the volcanic rocks, characterized by a high LILE/HFSE ratio and enrichments in LREE, indicate that they are typical of continental margin arc calc-alkaline volcanic rocks associated with the subduction environment. The ratios of Ba/Ta and Ba/La indicate that they are associated with volcanic arc-related magmatism. The Cretaceous volcanic rocks in Hampyeong area might be located in the Eurasian continental margin, related to the Pacific type tectonic environment during the Cretaceous times.