A review of four skarn deposits such as the Shinyemi Pb-Zn-Fe, the Sangdong W-Mo, The Geodo Cu-Au-Fe and the Yeonhwa Pb-Zn skarn ore deposits occurring at the southern limb of the Baegunsan Syncline in the Taebaeg Basin has been attempted in order to improve understanding of skarn deposits as well as to find any criterion to discover a hidden skarn ore deposit in the northern limb of the syncline. The Shinyemi Pb-Zn-Fe skarn deposit is different in the locality of limestone layers from other three skarn deposits which occur in the interbedded limestone of th Myobong Slate Formation and in the Pungchon Limestone of Cambrian age. The difference in the occurrence of this ore deposit is characterized by showing an olivine (forsterite) as a diagnostic mineral for magnesium-rich limestone. Most common minerals in these four skarn ore deposits are represented by Ca-garnet and clinopyroxene. A radical difference in anhydrous skarn minerals in the Yeonhwa Pb-Zn skarn is found by occurrence of pyroxenoids and a tendency of enrichment of manganese element in Ca-garnet and clinopyroxene. Abundant occurrence of quartz veins at the Sangdong W-Mo skarn and rhodochrosite veins at the Yeonhwa Pb-Zn skarn is a comparable difference in abundant hydrothermal vein systems between these two different ore deposits. A little occurrence of quartz in the Yeohwa Pb-Zn skarn orebody may indicate that W-Mo elements and Pb-Zn ore elements were transported as different ore solutions, the former as silicate-rich fluid and the latter as sulphur-rich fluid. The review of these skarn deposits has reached following conclusions: 1) Thick calcareous sediments (limestone), geological structure and a granitoid as a source rock are indispensable conditions for the formation of skarn ore deposits. 2) There must have been evolution of ore elements in the magma chamber during generation of the magma in the mantle. 3) A certain distance should be maintained from the source rock to the host rock (limestone) to form a huge skarn ore deposit like the Sangdong mine. 4) As the syncline structure is believed to have related with emplacement of granitoids as a source rock, so it is worthwhile to anticipate presence of hidden skarn orebodies at the northern limb of the syncline.