An apparatus for treating exhaust gas of an internal combustion engine, includes a feed conduit feeding aqueous solution, a hydrolysis catalytic converter connected to the feed conduit and an SCR catalytic converter through which exhaust gas flows. A rod-shaped heating element heats at least parts of the feed conduit and/or hydrolysis catalytic converter. The apparatus provides a compact structure of a feed conduit heated by a rod-shaped element and a corresponding hydrolysis catalytic converter, with which an aqueous solution containing urea can be evaporated and then hydrolyzed to a gas stream containing ammonia. This gas stream serves as a reducing agent in the SCR process. The compact configuration allows installation in very confined space conditions. The hydrolysis catalytic converter, through which exhaust gas does not flow, permits the volume of the hydrolysis catalytic converter to be decisively reduced, since significantly smaller mass flows of gas need to be hydrolyzed therein.