From the sensitivity of the FBG center wavelength changing with strain changes on the surface, the design of a FBG strain-based asphalt pavement pressure sensor is described by designing a special FBG asphalt box-film packaging structure. The compactness and simplicity of the device are achieved by using the corresponding package obtained from common available asphalt. Numerical analysis and experimental results show that the response of the sensor has good regularity for a wide range of travel (0MPa to 5.3312MPa). In the load range, the FBG center wavelength increases from 1548.264nm to 1548.346nm which shows a good correspondence with loads. Linearity, travel and sensitivity are experimentally determined by different packaging parameters. A design chart that includes the travel (0MPa to 5.3312MPa) and the sensitivity (15.3812pm/MPa) is finally proposed.