An actuating mechanism for three inlet valves of a cylinder of an internal combustion engine has three first rocker arms, each of which actuates an inlet valve and is actuated by a first cam for a lower revolution speed range, and two second rocker arms which are arranged between adjacent first rocker arms and are actuated by second cams for the upper speed range. The first and second rocker arms are coupled in the upper speed range so that the valves are actuated in accordance with the contour of the second cams.