Sewer maintenance warning device for road construction

The utility model discloses a sewer maintenance warning device for road construction, and relates to the technical field of road construction. The warning fence comprises two first baffles and two second baffles, a rectangular space is defined by the two first baffles and the two second baffles, containing cavities are formed in the first baffles and the second baffles, and a plurality of sequentially-stacked balance weight pieces are arranged in the containing cavities in a sliding mode. When the warning fence is used, the two first baffles and the two second baffles are enclosed to form the rectangular space, a sewer wellhead is protected, vehicles and pedestrians are warned, the weight of the whole warning fence is increased through the multiple balance weight pieces, so that the stability of the whole structure is improved, and the influence of the external environment is reduced; and stability is kept under strong convection weather conditions such as strong wind and rainstorm, the probability of positio