Photothermal therapy is a non-invasive, targeted, and new technology, but the existing photothermal therapy technology cannot monitor the temperature distribution of the target area in real time, and the open-loop laser control method not only increases the difficulty of treatment but also causes irreversible damage to normal tissues around patient''s lesion. This paper proposes a photothermal therapy method based on precise control of photoacoustic temperature. The proposed temperature imaging algorithm was studied, the concept of photoacoustic temperature sensitivity factor was proposed and a closed-loop temperature control algorithm was designed based on the factor. Finally, a new photothermal treatment system was designed based on precise control of photoacoustic temperature, and phantom experiments were conducted. The experimental results show that the photothermal therapy method based on the precise control of photoacoustic temperature can realize the non-contact accurate measurement and control function of the target zone temperature. The system adjustment time is within 10 s and the temperature control steady-state error is within 0.7 ℃. Additionally, the results show that the photothermal therapy method based on the precise control of photoacoustic temperature can be used as a more accurate and efficient auxiliary method in the field of photothermal therapy.