Water contamination by oil and grease compounds is the result of human activities and, in other cases, may be caused by accidents, reducing the possibility of its use and at the same time creating a major problem for the environment. This form of contamination of water sources has repercussions on the health of people, fauna and flora. There are various methods to decontaminate industrial wastewater so that it can be discharged into the receiving bodies so that it does not produce negative impacts or, in other cases, to reuse it. The objective of this research was to treat water contaminated with oils and grease generated in a mechanical service shop and radiators, using dielectric barrier plasma discharge technology, which has been gaining acceptance due to its environmental and efficiency advantages. With the application of this technology, 99.94% of the oils and greases (O&G) present in the contaminated water were reduced. The physicochemical properties of the water were also improved, establishing that the method was feasible and efficient.