Based on non-radiation transitions of heavily doped ions in the crystal fiber, a laser-pumped fiber-optic thermal tip has been developed for laser thermotherapy. Pumping by a 809 nm laser diode, the thermal tip generates a maximum temperature of 465° in air (with pumping power of 1124 mW) and 98° in egg white (with pumping power of 933 mW), which is high enough for laser thermotherapy. Meanwhile, the thermal tip shows satisfactory results in temperature stability, thermal response time, bio-compatibility, thermal impact resistibility, and chemical stability.