The invention discloses an urban road dedusting system. The urban road dedusting system comprises a substation and multiple automatic dedusting isolation fence units which are arranged among multiplelanes, and every two automatic dedusting isolation fence units are fixedly connected into a large isolation fence; an automatic dedusting isolation fence device is connected with the substation afterbeing in parallel connection with a cable. By means of the urban road dedusting system, by arraning the automatic dedusting isolation fence units among multiple urban lanes, urban air is intelligentlydetected and purified, raised dust and haze are reduced, and compared with a pure dedusting device, the urban road dedusting system is more economical and better saves energy.