Abstract: The motion of a ring on a paraboloid is a complex rigid body motion，which involves many obscuretheoretical knowledges． In this paper，an experiment of the motion of rings on a paraboloid is presented，and the motion modes of rings in different initial velocity directions are obtained，such as linear mode，clover mode，helicalmode． On the basis of fitting the constructed motion equation to the experimental data obtained by tracker software， the relationship between motion modes and the initial direction of velocity of rings isanalyzed． In the frame of rigid body motion theory，the angular velocity of the ring of special motional modes is discussed

Key words: paraboloid, ring, rigid body, angular velocity