A novel temperature sensor has been performed, which is based on the cascaded long-period fiber gratings. When only the temperature of the fiber between the LPGs is increased, the interferometric peaks will theoretically shift to longer wavelength and the loss will vary linearly. The temperature sensor is experimentally realized based on the above theory, which has the sensitivity of 0.0353 nm/℃ and 0.0684 dB/℃, respectively. This kind of temperature sensor based on the cascaded LPGs will have wide application prospect.