Fiber is one of the key factors for successful fracturing of high conductivity fractures in oil and gas wells. In order to optimize the fracturing technology and operation parameters for high conductivity fractures， laboratory physical model experiment with fiber as the main influencing factor was carried out to analyze the influence of fiber on proppant placement and channel occupancy in high conductivity fractures. The experimental results show： Adding fiber can significantly improve the sand carrying capacity and efficiency of fracturing fluid. The higher the fiber concentration is， the closer the proppant is placed to the middle and front of the fracture， which promotes the formation of long fractures in the fracturing process. The larger the constant adding proportion of fiber， the larger the occupancy rate of the fracture channel. However， the non-constant addition proportion of fiber provides the highest channel occupancy in the wedge-shaped way. In fracturing， the wedge-shaped addition method with high fiber proportion is helpful to form high conductivity fractures； over large or over small displacement will lead to less channel occupancy； and under the experimental conditions， the optimal displacement is 5.0 m³/h. The channel occupancy increases first and then decreases along the fracture extension direction with the maximum value in the middle of the fracture， and the minimum value at the crack opening. The fiber proportion and pumping rate do not affect the distribution trend of channel occupancy in high conductivity cracks.