This paper presents a front-unit-following control method for a snake-like robot using screw drive mechanism. The operators are required to command only one unit in the head, then commands for the rest of the units are automatically calculated to track the path of the preceding units. Asymptotic tracking error is investigated based on a Lyapunov approach for the case of a constant curvature. Furthermore, the effectiveness of the proposed method is investigated by computer simulations and laboratory experiments.