Abstract: To effectively remove hydrocarbon pollutants from mining diesel exhaust and optimize purification process parameters, a dielectric barrier discharge（DBD） non-thermal plasma reactor is constructed using ethylene as a representative simulant of hydrocarbons. Single-factor experiments combined with Box-Behnken response surface design are employed to systematically investigate the effects of discharge voltage, initial gas concentration, and inlet flow rate on purification efficiency. A quadratic regression model is established to optimize process parameters. Within the discharge voltage range of 0-35 kV, ethylene removal efficiency shows an initial increase followed by a decrease, reaching a maximum of 72% at 25 kV. Removal efficiency decreases significantly with increasing initial concentration （0-450 ppm）. Inlet flow rate exhibits a parabolic distribution within 1-6 L/min, with optimal performance at 3 L/min. The response surface analysis yields a quadratic regression model with R²=0.965. Factor importance ranking: inlet flow rate＞discharge voltage＞initial concentration. Optimal parameters: discharge voltage 19.54 kV, initial concentration 249.44 ppm, inlet flow rate 2.99 L/min, with predicted removal efficiency of 69.26% and experimental error of only 1.18%. NO_x addition enhanced ethylene removal by 10%-20%. The optimized parameters and synergistic purification mechanism provide theoretical foundation for engineering applications of DBD technology in mining diesel vehicle exhaust purification.