The automated methods to extract catchment properties from digital elevation data were described in this paper. They are related to the determination of flow direction in unit grid, the extraction of drainage networks, the extraction of catchment boundary, the treatment of flow directions and theextraction of drainage networks in pits and plat areas, the partition of subcatchment and the calculation of distributed catchment properties. The methods of determining flow direction in unit grid include single direction methods ,such as D8 method, Rho8 method, Lea method, DEMON method and D∞ method, and multitude directions methods. The algorithms of subcatchment properties including subcatchment length and subcatchment slope are different because of the different application. Several algorithms were mentioned in the paper. Also, an example was given about the extraction of catchment controlled by hydrology station. In which the D8 method was used to determine the flow direction of unit grid. And the result was satisfying basically.