An apparatus for preparing nano-carbon urea, characterized in that: a urea inlet pipe is connected to a conical nozzle located above a urea prilling tower; a spray device is installed under a natural ventilation window of the urea prilling tower, and the spray device is connected to an atomizing nozzle by means of a spray main pipe; the spray main pipe is connected to the atomizing nozzle, and is located in the urea prilling tower above a urea rotary sweeper; a bottom portion of the urea prilling tower is provided with a urea discharge funnel; the urea discharge funnel connects with and feeds into a roller drying apparatus, and an atomizing device being provided between the urea discharge funnel and the roller drying apparatus. In the present utility model, spray absorption inside the tower is combined with spray absorption and drying outside the tower, thereby increasing urea nano-carbon content.
