The utility model discloses a thermometer supporting cylinder for testing the temperature field distribution of an oil well thermal washing paraffin removal wellbore, which comprises an upper joint, asupporting cylinder body and a lower joint, and is characterized in that the supporting cylinder body is divided into an in-pipe thermometer cavity, a central circulating channel and an out-pipe thermometer cavity through an in-pipe thermometer baffle and an out-pipe thermometer baffle respectively; an in-tube liquid guide channel is formed in the wall of the in-tube thermometer baffle, and an in-tube thermometer is arranged at the end of the in-tube liquid guide channel. A lateral liquid inlet hole is formed in the wall, corresponding to the cavity of the outside-pipe thermometer, of the supporting cylinder body, an annular liquid guide channel is formed corresponding to the lateral liquid inlet hole, and the outside-pipe thermometer is arranged at the end of the annular liquid guide channel; and a one-way valve is arranged in the hollow liquid guide channel. Due to the fact that the temperature conduction channel of the device has a protection function, a circulation overflowing channel of liquid is not affected, and the device has the function of testing the oil sleeve annulus temperature and the temperature in the oil pipe in the operation process.