The invention discloses a method for determining the reasonable pressure level of an inversed nine-point pattern advanced water injection formation of a low-permeability reservoir. The method is characterized by comprising the following steps: (1) determining the reasonable pressure level of the advanced water injection formation of the low-permeability reservoir to calculate required parameters of an oil well and a water injection well; (2) building an advanced water injection well productivity calculation model of the low-permeability reservoir; (3) building a reasonable pressure level calculation model of the inversed nine-point pattern advanced water injection formation; and (4) solving the reasonable pressure level calculation model of the inversed nine-point pattern advanced water injection formation of the low-permeability reservoir. Accurate quantitative evaluation of the reasonable pressure level of the inversed nine-point pattern advanced water injection formation of the low-permeability reservoir can be achieved, the operability is high, and development practice of an advanced water injection oil field can be effectively guided.