To provide a slat conveyor apparatus in which course change path parts are moved without inverting the upper and lower sides of slats to eliminate the need for an expensive pitting work, wherein the slats can be held horizontally by a simplified configuration on the course change path parts at front and back ends in the direction of conveyance, whereby the length of the working process does not become shorter, and a required inverting action can be made by a simplified configuration.Endless chains 2C are connected to front ends of the slats 3 in a traveling direction F, a supported means B to be supported at the course change path parts C1 is provided to back ends of the slats 3 in the traveling direction F, a movable supporting means C is provided to the course change path parts C1 to support the supported means B from below and hold the slats 3 in the horizontal posture, and the movable supporting means C repeatedly travels back and forth in the vertical direction in conjunction with movement of the endless chains 2C and moves to a position at which to support the supported means B from below only when the supported means B passes through the course change path parts C1.