A novel long-period fiber grating (LPFG) is fabricated in common communication optical fiber by using a edge-written exposure method with high-frequency CO2 laser pulses. Studies show that this kind of long-period fiber grating has refractive index disturbance mainly in cladding of optical fiber, and its excess loss is less than 0.5 dB. Experimental results of the refractive index characteristic show that it has a resonant peak shift of 15.52 nm when the surrounding refractive index varies in the range of 1.41～1.45, which is three times higher than that of a conventional long-period fiber grating due to especial refractive index disturbance. The novel long-period fiber grating can find important applications in the field of optical sensing.