Abstract: It was found during the oil test of Well Gaotan-1 that the temperature of bottomhole fluids increased with production, which cannot be explained by existing test data and analysis methods. Therefore, based on the conservation equations of mass and energy and according to the seepage flow law of high-temperature fluid in the formation, the flow law in the wellbore and the heat transfer during the seepage and flow, a model of thermal flow coupling between the wellbore and reservoir was established, and a method for inversion of formation temperature in high-yield wells was proposed by analyzing transient temperature data. This method was used to invert the production pressure and temperature data of Well Gaotan-1, and the temperature curve of the inversion was highly consistent with the measured temperature curve of Well Gaotan-1, which explained the phenomenon that the bottomhole fluid temperature increased with the production. The study indicated that the proposed new method for the inversion of formation characteristic and temperature of high-yield wells could quantitatively analyze the formation thermodynamics and seepage parameters, and in that way, determine the fluids producing location of high-yield wells, and provide important basis for production string safety appraisal, field production decision-making, reservoir recognition and reserves calculation.