The invention discloses a quantitative characterization method for full-scale pore throats of a compact sandstone oil reservoir. The method comprises the steps of 1, according to a gas-measured permeability value of a rock core, determining a test method for testing pore throat parameters; 2, carrying out corresponding experiment tests to obtain pore throat radiuses and pore throat content changecurves; 3, performing unified processing on different test results; 4, drawing the different test results in the same coordinate system to obtain cross curves; 5, calculating intersection points of linear segments determined by the curves to serve as new connection points; 6, re-drawing pore throat distribution curves after connection to obtain relation curves of the radiuses of the full-scale pore throats and the volumes of the pore throats; and 7, performing re-calculating to obtain average pore and throat radius parameters, and calculating relative contributions of the pore throats with different scales to the permeability. According to the method, a thought of effectively fusing different experiments and various test results is innovatively proposed, and a fusion method suitable for quantitative characterization of compact sandstone pores is proposed, thereby achieving full-scale representation of pore throat distribution.