The surface modifications of a synthetic vulcanized styrene-butadiene rubber (RI) using a chemical treatment [halogenation with trichloroisocyanuric acid (TCI)] and a treatment with oxygen plasma were compared. Treatment of RI rubber with 2 wt% TCI produced greater surface modification than the oxygen plasma and the modification was extended over a thicker region of the rubber when it was treated using TCI. The degree of oxidation obtained with only 1 min of oxygen plasma treatment was greater than that obtained by chlorination with different amounts of TCI. This agreed with the improved interaction among polar groups evaluated from the higher acid-base contribution to the surface energy of the oxygen plasma-treated RI rubber surface. However, higher T-peel strength values and more noticeable cohesive failure in the rubber were obtained for joints produced with chlorinated R I rubber than for those produced with oxygen plasma-treated R I rubber, due to the creation of a less rough and weaker oxygen plasma-treated surface.