The utility model relates to an external cable ditch is with rain-proof apron, these cable trench cover top surface both ends are equipped with the guiding gutter, and the apron is equipped with the capable sealing strip of T with cover connection department, and T type sealing strip covers the guiding gutter and hugs closely the apron top surface, still can be equipped with the vent on the wall of apron both sides, and the vent outside-in bore on the apron reduces or equals, and apron lateral wall both ends border can also be for the U type groove design that each other be the symmetry, and two apron are through U type groove gomphosis connection. This cable trench cover reasonable in design can effectively prevent the entering cable pit of liquid such as rainwater, and sufficient draught area has been guaranteed to the vent of apron both sides, ensures that the cable pit is dry good with the cable radiating effect, ensures the drying in the cable pit, and apron installation back is firm, is difficult to move the aversion, and low in production cost, and difficult damaged change has reduced use cost.