The method of fabricating structural long period grating (LPG) in a photonic crystal fiber (PCF) with periodically collapsed holes along the length of the fiber by use of arc discharge is proposed. The influence of the fiber structural parameters, involving the grating period, the number of periods, the refractive index and temperature, on transmission characteristics is further studied. The research results indicate that the transmission characteristics of the manufactural LPG can be tuned by the grating period and the number of periods regularly. The refractive sensitivity and the temperature sensitivity are 420 nm/RIU (RIU is refractive index unit) and 7.86 pm/℃, respectively, which is found to be highly sensitive to refractive index while weakly sensitive to temperature. These unique properties can bring many potential applications in the field of optical fiber sensor with largely reduced cross-sensitivity.