The invention relates to a road construction sign support which comprises two support bodies for installing a warning plate. The two support bodies are symmetrically arranged, the symmetrical verticalfaces of the support bodies are provided with symmetrical insertion grooves, and two symmetrical connecting bases are arranged between the symmetrical transverse faces of the two support bodies. Theconnecting bases are connected through a connecting rod, the tail ends of the connecting bases are connected with the support bodies, and the connecting bases are movably connected with the connectingrod and the support bodies through hinges respectively. According to the road construction sign support, the insertion grooves are formed in the two symmetrical supports, the warning plate can be inserted in the insertion grooves, the corresponding warning plate can be installed according to actual requirements in use, flexibility is high, the support bodies are connected through a movable hinge,folding is convenient, placement space is saved, the distance adjustment of the supports is realized by designing the telescopic connecting rod, the sign support can be conveniently used for warningplates of different lengths, the whole sign support can be conveniently carried due to the design of the support bodies and wheels at the bottom of the connecting bases, and the sign support can be conveniently used in the road construction process.