A driving force transmission apparatus includes: a first cam mechanism that converts rotational force from a housing into first cam thrust force used as clutch force of a main clutch when the first cam mechanism is actuated through clutch action of a pilot clutch; and a second cam mechanism that is actuated prior to conversion of the rotational force into the first cam thrust force by the first cam mechanism, and that generates second cam thrust force for reducing an interval between clutch plates of the main clutch. The second cam mechanism includes an input cam member that rotates upon receiving rotational force used as actuating force of the input cam member from a cam actuating driving source, and an output cam member that generates the second cam thrust force between the output cam member and the input cam member and outputs the second cam thrust force.