Abstract: Load characteristic tests were conducted by installing an exhaust gas recovery smoke engine in exhaust pipe based on a YN series 38CRD2 diesel engine．Influence of engine speed, nozzle flow rate and aerosol concentration changes on atomization effect of smoke machine were studied．Exhaust energy recovery efficiency was obtained by changing temperature at the front and rear ends of exhaust pipe and fuel consumption before and after installing smoke machine．Test results indicated that when engine speed was 2400 r/min, droplet size was the best．Under constant engine speed conditions, when concentration of smoke agent was 30%, droplet size was the best．When nozzle flow rate was 7.5 L/min, nozzle atomization was better．After installing smoke machine, when engine speed was between 2200 to 2400 r/min, engine operated stably and droplet size of smoke machine was uniform．By collecting temperature data from front and rear ends of engine exhaust pipes, it was calculated that exhaust gas recovery and reuse rate was 11%, which meaned that 88 g diesel fuel was used more frequently．Fuel utilization efficiency was improved and energy saving and emission reduction was achieved．It provided a new direction for multifunctional development of agricultural machinery．