A 3-D coordinate measuring machine (CMM) touch trigger probe based on fiber Bragg gratings was developed. The sensing system and the control box of the probe were described respectively. The error of the probe may arise from the mechanical structure, the sensing signal demodulation system, the measuring speed and the approaching distance during the process. Experiments showed that probe positioning accuracy in single direction could reach 20nm, sensitivity came up to 50nm and a measuring force was less than 5mN. 