In order to measure the pile friction,pile tip resistance and soil re sistance of the open pipe pile during sinking,a double-walled open mode pipe pile with fiber Bragg grating (FBG) sen sor is designed. A fiber grating sensor theoretical sensitivity coefficient and experimental sensitivity coeffici ent strain calibration method is proposed in view of the application of FBG sensors in the model pipe pile test. Combined with the theoretical analysis, the finite element Abaqus stress distribution of the model pipe pile is simulate d and analyzed before the FBG strain sensor is encapsulated. The double-walled open model pipe pile has no influence on the FBG strain sensor and the experimental strain measurement accuracy is improved.The calibration experiment of FBG strain sensor after the model pipe pile encapsulation is carried out by every step loading and unloading of 200με,and it is loaded for 5times.The strain sensitivity coefficients of FBG sensor encapsulated on interna l and external tubes are 2.15pm/με and 2.24pm/με,respectively,with line arity greater than 0.999.At the same time,the method is simple and easy to operate,and is suitable for the calibration of fiber grati ng strain sensor before the model pipe pile test,which lays the foundation for the application of FBG sensors in the e xperiment and engineering.