The invention discloses a laser fiber core diameter intelligent identification device. The device mainly comprises an infrared luminous receiving module, an optical signal reflecting board, a single-chip microcomputer processor and the like. As the holmium laser therapy apparatus adopts the energy of optical fibre transmission to treat lesions, with the continuous development of the technology ofthe holmium laser therapy apparatus, large power holmium laser therapy apparatus appears; as the therapy apparatuses with different powers require of being provided with optical fibre with different core diameters, an optical fiber core diameter intelligent identification system is required to identify the core diameter of optical fiber and control the output power of the laser therapy apparatus,thus the optical fibre can not be damaged accidentally. As the identification device adopts the new technology, the core diameter of optical fibre can be identified intellectually, the transmission power of the optical fiber with different core diameters can be controlled and the situation that optical fiber is damaged caused by inputting large power in the optical fiber with small core diameter can be avoided, thus ensuring the operation of the device.