Enzymatic browning of damaged tissues of fruits and vegetables occurs from the oxidation of phenolic compounds and contributes significantly to quality loss. The primary enzyme responsible for the browning reaction is polyphenol oxidase (PPO). PPO from Domat olives was extracted and purified through (NH₄)₂SO₄ precipitation, dialysis and ion exchange chromatography. Optimum pH and temperature for olive PPO were found to be 4.5 and 30 °C, respectively, using 4-methyl catechol as substrate. Km and Vmax values for olive PPO using 4-methyl catechol as substrate were found to be 14.52 mM (r2= 0.985) and 1.78 Abs/min, respectively. Of the inhibitors tested, the most potent inhibitors were L-cysteine and sodium disulfite. The Z and Ea values obtained in this study were 18.6 °C (r2 = 0.953) and 121.0 kj/mol (r2= 0.950), respectively.