Engine emission test rack

The invention provides an engine emission test rack; the engine emission test rack comprises an engine exhaust pipe, a tail gas discharge pipeline, a three-way valve or a butterfly valve, and an exhaust post-process device; one end of the engine exhaust pipe is directly connected with the engine; the other end of the engine exhaust pipe is connected with the exhaust post-process device and the tail gas discharge pipeline through one of the three-way valve or two of the butterfly valves; the outlet port of the exhaust post-process device is connected with the tail gas discharge pipeline. After starting the engine, the switching between the engine original emission test and the exhaust post-process test can be implemented by controlling the three-way valve or the butterfly valves. The provided engine emission test rack is short in infrastructure construction and onsite debug periods, wide in extended application range; the integration of the engine original emission test and engine post-process test can be simultaneously achieved; the engine emission test rack can be widely applied in fields such as schools, factories, enterprises, engine and finished automobile development, test and authentication.