The thin-film pressure sensor in prosthetic tactile measurement has problems of low accuracy, poor linearity and high hysteresis. To address these issues, a tactile sensor based on the fiber Bragg grating (FBG) is studied. It can be easily installed on the fingertip. Firstly, a sensing unit is designed to convert the external force into an axial one needed by the FBG. Secondly, the finite element simulation is utilized to optimize the structure of the sensing unit. In this way, the sensitivity of pressure measurement is improved. Finally, the FBG tactile sensor is prepared and stuck to the prosthetic fingertip. Experiments on performance calibration, comparative analysis, and grasping application are carried out. Results show, for the FBG tactile sensor, the sensitivity is 0. 103 8 nm/ N, the linearity R 2 is 0. 998, the repeatability error is 1. 32% , and the hysteresis error is 2. 19% . Compared with the thin-film pressure sensor, the designed FBG sensor has advantages of linearity, stable repeatability, and hysteresis.