The invention discloses a method for discriminating the blocking type of a window dam in a debris flow interception process and application thereof. According to the method, the blocking type of the window dam is discriminated according to the type of debris flow, the grain size d 95 of debris flow solid matter, the opening width b of the window dam, the opening height h of the window dam, the total area S0 of the cross sections of the openings of the window dam, the cross section area S below the effective height of the window dam within channel width. The method can be used for verifying the blocking type of the window dam or guiding the opening design of the window dam. Compared with the prior art, the opening width, the opening height and the total opening area are taken into consideration, the influences of the opening width, the opening height and the total opening area on the blocking type of the window dam are reflected completely, and the blocking type of the window dam can be distinguished reasonably. Further, the method for discriminating the blocking type of the window dam in the debris flow interception process supplies basis to window dam design and meets the actual engineering demands.