Abstract: The big floor undulation at 1201 working face in Shanzhai Mine brings various unfavorable factors to the normal mining. Radiowave penetration method was used to detect abnormal geology areas in detail. the floor approaching to the bulging section was gradually lifted in advance during the mining process, which made the working face show a roachback shape up-down dip mining. Control measures about scraper conveyers and hydraulic supports were made to realize the high efficient mining.