The present invention provides an AHP-based method for natural disaster risk assessment of a power grid. The method comprises: performing statistical analysis on historical disasters and historical weather forecast information in a region in which an assessed power grid is located, and constructing a risk assessment indicator system through harm identification and vulnerability analysis; constructing a natural disaster risk estimation model of the assessed power grid by using an improved analytic hierarchy process; determining a relative weight of each assessment indicator by using the analytic hierarchy process; determining a risk value the of each assessment indicator based on a preset risk assessment standard; calculating a comprehensive risk value by using the risk value of each assessment indicator and the relative weight of each assessment indicator as an input value of the natural disaster risk assessment model; and establishing a risk level standard so as to obtain a final risk level of the assessed power grid. Impacts from the natural environment and the social environment are comprehensively considered, and comprehensive assessment that combines qualitative and quantitative assessment is performed on the natural disasters of a power grid, thereby providing a theoretical basis for ensuring safe and stable operation of the power grid and for reducing economic loss.