The invention discloses a temperature controller compensation device for a large-sized power transformer. The temperature controller compensation device for the large-sized power transformer comprises a cylinder body (2), a connecting rod (1), a leaf spring (3), an adjusting nut (4), a spring (5), a cylinder body cover (6) and a push rod (7), wherein a containing groove (8) is formed in the cylinder body (2), the connecting rod (1) is arranged at the bottom of the cylinder body (2), the leaf spring (3) is arranged on the innermost portion of the containing groove (8) of the cylinder body (2), the free length of the leaf spring (3) changes along with changes of the temperature in a linear mode, one end of the adjusting nut (4) is connected with the interior of the leaf spring (3) in a sleeved mode, the spring (5) is connected with the other end of the adjusting nut (4) in a rotary mode, the cylinder body cover (6) seals the containing groove (8), a hole (9) is formed in the cylinder body cover (6), and the push rod (7) is connected with the adjusting nut (4) in a threaded mode, and penetrates out of the hole (9) of the cylinder body cover (6). Due to the fact that the free length of the leaf spring changes along with the changes of the temperature, the leaf spring pushes the adjusting nut to drive the push rod to contract or stretch out, the purpose of temperature compensation is achieved, and the temperature controller compensation device for the large-sized power transformer is simple in structure, simple in manufacturing technology, good in reliability, high in accuracy of temperature compensation, high in qualified rate and low in cost.