The invention discloses a method for observing preferential flows in arid and semi-arid alpine regions, which belongs to a technical measure for researching forest hydrology processes, water resources and sloping-field runoff characteristics. In a technique and a method for observing preferential flow observing fields in arid and semi-arid alpine regions disclosed by the invention, according to the theories of forest ecology and forest hydrology, the occurrence regularity and development regularity of snowmelt runoffs are observed and studied, and through observation, research and analysis, the change rule of preferential flows under the conditions of different weather conditions, different forest vegetations, different forest coverage rates, different manual acting modes and different slope positions and directions is revealed, thereby finding effective ways of increasing the flow rate of preferential flows, developing and rationally utilizing water resources, making up the flow rate of river channels in dry seasons, relieving the contradiction of water utilization for spring ploughing in the middle and lower reaches of rivers, and solving practical problems which are badly required to be solved in current agricultural production.