Abstract: A position controlling mechanism is provided in the present invention, which comprises a plurality of bar linkage with multiple degrees of freedom (DOF) for controlling a specific position of the bar linkage to move arbitrarily on a curved surface according the input movement of the bar linkage of the position controlling mechanism. Meanwhile, an apparatus for controlling eye movement is also provided by combing the position controlling mechanism and an eyeball assembly arranged on the specific position of the bar linkage. By means of the position controlling mechanism, the eyeball assembly can be moved toward any direction so as to increase the diversity of the facial expression of a doll.