The invention discloses a tubular blast furnace soft water evaporative air cooling system and a tube scale treatment method thereof, and belongs to the technical field of blast furnace ironmaking production. The tubular blast furnace soft water evaporative air cooling system comprises a base, a shell, a cooling tube bundle cluster and induced draft cooling towers, wherein the shell is located over the base and fixedly connected with the base; the cooling tube bundle cluster is fixedly installed in the shell and arranged horizontally in a layered mode; the induced draft cooling towers are arranged on the shell and fixedly connected with the shell. The top ends of the induced draft cooling towers are completely open. The installed capacity and the production cost are lowered by replacing fans with a draft induction function with the induced draft cooling towers, so that the situation that the fans are replaced frequently due to vulnerable motors is avoided, and the tubular blast furnace soft water evaporative air cooling system can operate for a long time. According to the tube scale treatment method of the tubular blast furnace soft water evaporative air cooling system, the whole system can be descaled irregularly during operation, the system can also be thoroughly descaled during the shut-down period, descaling is flexible and maneuvering, the treatment effect is thorough, the heat exchange and cooling effects of the whole system are improved, and the continuous operating time and the service life are prolonged.