A whisker sensor includes an upper circuit board, a lower circuit board, a flexible whisker, and a magnet. The magnet is fixed to the flexible whisker through a central through hole, and the location of the magnet changes with the swinging of the whisker; the upper and lower circuit boards are identical in shape and size, and are connected through an upright column. A circular hole is formed at the center of the upper circuit board, four Hall sensors are symmetrically distributed on the edge of the circular hole, and the displacement of the whisker in X and Y directions can be obtained by detecting the change in magnetic field generated by the change in location of the magnet; a contact sensor is mounted on the lower circuit board, and is connected to the whisker through a connecting piece, to detect displacement of the whisker in the Z direction.