The invention discloses an anisotropic ridge surface roughness factor acquisition method and an application thereof, and belongs to the technology field of irrigation and water conservancy. The method comprises: two experimental strip fields which are respectively parallel to length and width of a target ridge field are pre-selected, and first surface flow advancement process data of two experimental strip fields are separately acquired. The target ridge field can be interpreted as a square. According to the first surface flow advancement process data, an one-dimensional hydrodynamic border irrigation model is adopted to separately obtain two anisotropic ridge surface roughness factors, and the two factors are substituted into an elliptic equation satisfied by the anisotropic ridge surface roughness factor, the anisotropic ridge surface roughness factor of the target ridge field is calculated and obtained, and the anisotropic ridge surface roughness fator comprises ridge surface roughness components which are separately paralled and vertical to ridge surface shallow ridge and crop cultivation directions of the target ridge field. The anisotropic ridge surface roughness factor can truly reflect resistance from ridge field surface to water flow, so that the above facilitates the improvement of simulation precision of ground irrigation water dynamics, and preciser irrigation performance indexes can be obtained.