Globally, there is still a demand for effective removal of industrial pollutants using modern treatment technologies. Therefore, to achieve industrial implementation, treatment efficiency and energy demand, at present the new Non-Thermal Plasma (NTP) technology is adopted to treat the dairy industry pollutants. Falling Film Dielectric Barrier Discharge reactor (FF-DBD) is developed whereas the reactor is further characterized by the various operating parameters including electric field, gas source, flow rate and pH for the removal of COD and lactose content for different experimental conditions. In this present study, experimental works are carried out in ‘lab-scale experimental hardware to analyze the degradation efficiency of dairy effluent based on COD and lactose. For the maximum of 68 % and 75.56 % of COD and lactose removal is achieved at the maximum voltage of 30 k,Vp-p. Moreover, the interaction between COD and lactose is analyzed by using ANOVA and the p-value is < 0.001. Comparing to the air, oxygen as a discharge gas in a DBD reactor gives more treatment efficiency because it produces more oxygen-based oxidative species. Further the 2D - simulation model is employed to find the velocity profile of effluent inside the FF-DBD reactor.