The invention discloses a vacuum temperature adjustment impregnation technology used for a power transformer, wherein the impregnation technology is based on a vacuum temperature adjustment impregnation device; the impregnation technology comprises the steps of vacuumizing the interior of a semi-finished product of the power transformer, and maintaining the pressure in a vacuum cavity to be 50Pa;heating the interior of the semi-finished product of the power transformer to be 90 DEG C, heating an oil cavity to be 40 DEG C, wherein the time is maintained for 24 hours; reducing the temperature in the semi-finished product of the power transformer to the optimum impregnation temperature; and slowly injecting insulating oil into the semi-finished product of the power transformer until a winding of the semi-finished product of the power transformer is immersed in the insulating oil, starting a circulating oil pump until the insulating oil can flow from top to bottom in an oil tank of semi-finished product of the power transformer, wherein the maintaining time is 8-10h; a viscosity meter is arranged in the oil cavity and used for detecting the kinematic viscosity of the insulating oil; the oil flow rate of the circulating oil pump is kept at 1.5-2m/s. By virtue of the vacuum temperature adjustment impregnation technology used for the power transformer, the impregnating degree and theimpregnating rate of oil paper of the power transformer are increased, and impregnating time is shortened.