Research conclusions:Through researching, it isunderstood thatGypsum karstbreccia has specific horizon, locating at the first segment in each formation of the medium series ofOrdovician System. Mostof it is special flexible rock with greatdifferences in strength. According to the difference of cementation, gypsum karst breccia is classified as slight cementation, weak cementation, moderate cementation, strong cementation. According to the grain composition, the material componen,t its forming environmentand the cemented degree, the gypsum karstbreccia can be divided of four kinds: the boulder shape, stone coated bymud shape, shapewith the gravel and the hard soil shape. The engineering geological survey should be strengthened forFengfeng Fm ofOrdovician system.