Based on the characteristic of the fiber grating wavelength absolute encoding, the vertical sensing measurements of the stress, displacement have been realized by means of the improving the structure design of the free end of the cantilever beam. The theoretical analyses and the experimental results indicate that the magnitudes and the vertical directions of the mechanical quantities, such as stress, displacement and etc. can be sensed and measured through monitoring the value and direction of the wavelength shift of the fiber grating that is bonded to the near fixed end of the cantilever beam. In the vertical directions, the experimental sensitivities of the stress are 1 87 nm/N and 3 40 nm/N, the experimental sensitivities of the displacement are 0 23 nm/mm and 0 41 nm/mm, respectively.