After more than ten years of effort, especially since 2003, great progress have been made on detection and forecast of faults, underground rivers, karst caves and ground water in tunnel construction with great supports from national administration. Based on the actual survey cases, the author introduces the complete technology of land sonar method, transient electromagnetic method and ground penetrating radar method, which have achieved good effect in theoretical researches and actual forecasts in determining the threedimensional locations of faults, survey of ground water and karst caves.