Abstract: A urea solution mixing chamber for a diesel vehicle that increases a purification rate of NOx by increasing a vaporization rate of a urea solution by use of a urea solution vaporization component, includes a flow guide configured to guide a flow of exhaust gas while collecting the flow of the exhaust gas toward a catalyst, a urea solution injector disposed rearward of the flow guide and configured to distribute and inject a urea solution, an impactor provided on an internal surface of the flow guide configured to collect the exhaust gas, the impactor being configured to atomize the urea solution injected from the urea solution injector, and vaporization fins configured to vaporize the atomized urea solution by bringing the atomized urea solution into contact with the vaporization fins and mix the vaporized urea solution with the exhaust gas.