The invention provides a high-precision passive positioning method for jointly estimating signal parameter and a position. Based on a DPD-unknown algorithm, the parameter of transmitted signals and a position are jointly estimated, so that positioning performance can be improved. A base station carries out short-time Fourier transformation on received observation signals, so that the instantaneous frequency of the received signals can be estimated; and a grid search method is adopted to jointly estimate the waveform parameter of the transmitted signals and the position of a target. According to the method of the invention, the waveform information of the transmitted signals is fully mined; according to the time-frequency characteristic of linear frequency modulation signals, and based on the short-time Fourier transformation, the signal parameter and the position can be jointly estimated, and therefore, the positioning performance can be greatly improved with the help of the signal parameter; and the time-frequency analysis tool, namely, the short-time Fourier transformation is adopted, the calculation amount of the method is at a reasonable level, and the calculation cost of the method is small.