The invention belongs to the technical field of grid construction engineering cost, and especially relates to an AHP analysis model for analyzing the impact on the construction cost of a power grid from the change of sales tax into VAT (value-added tax). The construction of the analysis model comprises the following steps: S1, making the fundamental assumption according to the main boundary conditions of the impact on the construction cost of the power grid from the change of sales tax into VAT; S2, taking the change amplitude of construction cost before and after the change of sales tax intoVAT as a balance index, carrying out the layer-by-layer decomposition of the cost to an element layer with a determined rule, and obtaining an AHP analysis model for the cost of a transmission and transformation project; S3, maintaining two variables of the AHP analysis model, and analyzing the impact on the investment and cost of the grid construction project from the two variables through a sensitivity analysis method; S4, selecting several project cases which has complete the research feasibility inspection for verifying the AHP analysis model. According to the invention, the AHP analysis model is used for the sensitivity analysis of the impact on the construction cost, and can enable a person to visually observe the impact on the construction cost from the change of sales tax into VATin the building industry.