Abstract: In order to study the dynamic evolution law of the development height of overburden water conducting fractured zone, taking 2⁻² coal seam in Xiaobaodang Mining Area as the research object, the dynamic development height of water conducting fractured zone was studied by theoretical analysis, similar simulation experiment and case verification; a prediction method of dynamic development height of water-flowing fractured zone based on curvature deformation of overburden strata is proposed by using the theoretical formula of predicting the movement and deformation of upper strata with probability integral method. The research shows that the subsidence coefficient of the upper strata of the water-conducting fractured zone is a piecewise function related to the deflection and the height of the lower free space. The curvature deformation of the upper strata is the key factor to determine the development height of the water-conducting fractured zone. The development height of water-flowing fractured zone is related to the advance length of working face; the theoretical prediction of the development height of the water conducting fractured zone in 2⁻² coal seam of Xiaobaodang Mining Area is 160.8 m, the development height of the similar simulation experiment is 155 m, and the development height of the field measurement is 152.01-175.57 m.