The utility model discloses a road drainage system in sponge city, including the basic unit, the road surface has been laid to the upper end of basic unit, the road surface is constant angle degree slope, pass through on the road surface and be equipped with the installation piece, the upper end of installation piece is equipped with the mounting groove, install the permeable formation in the mounting groove, the lower extreme of installation piece is fixed with first water catch bowl, the lower extreme both sides of first water catch bowl all are fixed with the inlet tube, the one end of inlet tube all is fixed with the second water catch bowl. The utility model discloses a discharge and permeate clean rainwater to the filtration of rainwater the road rainwater to fix the well lid, it often can be because reasons such as extrusion misplaces to have solved manhole cover, and the possible emergence scheduling problem that leads to the accident to current the playing an important role that the road is normal, and reduced the probability of risk occurence of failure, is current safer, and simple structure conveniently operates, the suitable popularization.