Abstract: The loessic gullies not connected directly with river systems are widely spread in the Q_2-4 loess of Fenwei Basin. The loessic gullies are directional, independent, regional and intersected with the network. The strike of many groups of gullies presents a clockwise deflection from west to east. Field investigation indicates that the loessic gullies were formed by ioessic tectonic joints constantly suffered from ground water corrosion. Therefore, the sprea ding directions and developing degrees of both tectonic joints and gullies are correspondent. The neotectonic stress field of Weihe Basin determined by loessic conjugate shear plane corresponded with gully network coincides essentially with the neotectonic stress field determined by river systems and earthquake. The study of loessic gully network is of great significance for searching out groundwater, researching soil erosion, recovering neotectonic stress field and predicting earthquake.