Optical fiber sensor studying is one of the most important research project for several dozens year,the discovery of optical fiber bragg grating sensor has brought a new technological breakthrough for the optical fiber sensor.The cross-sensitivity is the key problem of fiber grating sensors.The development of the fiber grating strain-temperature sensor is presented in this paper.The physical mechanics of simultaneous measurement of strain and temperature are analyzed.And one method which measured strain and temperature simultaneously based on the sample fiber Bragg grating is proposed.