Abstract: A hitch-mounted warning sign apparatus for a vehicle for alerting approaching motorists of road work being conducted in the area. The hitch-mounted warning sign apparatus for a vehicle includes a receiver hitch being adapted to be mounted to a vehicle and including a tubular member having an open end, a bore extending therein through the open end, and a hole being disposed through a side wall of the tubular member; and also includes a sign support assembly being fastenably mounted to the receiver hitch; and further includes a fastener being removably extended through the hole of the receiver hitch for fastening the sign support assembly to the receiver hitch; and also includes a light-emitting assembly being attached to the sign support assembly; and further includes a sign assembly being mounted to the sign support assembly.