To explore the applicability of the fiber Bragg grating (FBG) sensing technology in the penetration characteristics of jacked piles with different pile diameters, FBG strain and pressure sensors were calibrated using a tensile testing machine and sand calibration method, respectively. The linearity and testing accuracy of sensors are found to be good. Further, the jacked pile test of the test model with sensors was conducted in a large model box. Experiment results indicate that the requirement for FBG sensing technology to test the penetration characteristics of jacked piles with different pile diameters can be satisfied. FBG sensors demonstrate high linearity and sensitivity; moreover, the test data are reliable, and the installation method of the sensor is feasible. During the penetration process, FBG sensors can dynamically and accurately monitor the pile driving force, pile end resistance, side friction resistance, pile axial force, and unit side friction. Moreover, they can reflect the differences and change rules of penetration characteristics of the model piles with different pile diameters in the process of isostatic pressing.