In a Certain Mining Engineering, it’s Needed to Collect the Ore Bearing Sandy Soil with Certain Thickness from the Ground Surface. in Order to Realize Accurate Collection, it’s Needed to Control the Collecting Thickness Strictly. the Application of Contacting Type Landform Detecting Method in the Engineering Machinery Was Discussed, and a Kind of Mechanical Contacting Landform Detector Was Developed for the Alluvium Landform of Mining Area in Gobi with Loose, Rough and Uneven Ground Surface. the Landform of Soft Sandy Soil Can Be Detected by Controlling the Contact Pressure between the Depth Wheel of the Detector and the Ground Surface. with the Use of PID Control Technology with Wave Filtering, the Real-Time Detection Accuracy of the Detector for Mixed Sandy Soil Ground Surface Reaches ± 3mm. this Detector Is Specially Used for Milling, Planing and Collecting Device, Achieving Uniform Thickness Collection of Ore Bearing Sandy Soil in Rolling Topography Condition.