The invention provides a laser-welding fiber grating surface temperature sensor which comprises a fiber, a metal substrate and a bottomless nonmetal framework. The fiber comprises a fiber grating plated with a metal layer and signal transmission tail fibers at the two sides of the fiber grating. The two ends of the fiber grating are fixed to the metal substrate through laser welding; the signal transmission tail fibers are respectively sleeved by a fiber protection sleeve pipe; the bottom portion of the nonmetal framework is fixed to the metal substrate; the nonmetal framework is provided with through holes for allowing the fiber protection sleeve pipes to pass through; and the nonmetal framework is internally filled with paste-like heat-conduction silicone grease. The fiber grating is subjected to coating layer removing and metal film layer plating, and is then, fixed to the metal substrate through the laser welding method, thereby realizing full metal packaging of a temperature sensing portion of the whole sensor, and overcoming creep and aging of adhesives in a conventional adhesive substrate fiber grating temperature sensor; and compared with glass welding, the laser-welding fiber grating surface temperature sensor has higher mechanical strength, and can bear higher test temperature; and fiber grating object surface temperature measurement long-term reliability and stability are improved on the whole.