In order to accurately determine the extent of the ground fissure and the extent of the hazard of the Longyao ground fissure,the influence width of the ground fissure activity zone in the area was analyzed through the field survey results combined with trenching and physical simulation tests. The results show that the Longyao ground fissure has a total length of about 35 km and is distributed in a linelike manner. It has the characteristics of normal tensile extension,left-lateral rotation and east-lateral right-lateral strike-slip movement. The distribution of fractures in the ground fissure disaster area and the Neiqiu-Julu (Longyaonan) is basically coincident,indicating that the Neiqi-Julu (Longyaonan) fault is the main fault of the Longyao ground fissure. The cracks in the Longyao ground fissures are distributed along the ground. The main deformation zone of the ground fissure is 0~15m on the upper plate and 0~11m on the lower plate. The micro-deformation zone is 16~46m on the upper plate and 12~28m on the lower plate.