The diffusivity of ozone in water was determined experimentally by measuring the rate of ozone absorption into an aqueous laminar liquid jet. Penetration theory was used to interpret the results. Experiments were conducted over the temperature range of 10 degrees C to 45 degrees C. The results for diffusivity were correlated by an Arrhenius function for temperature dependence with a maximum deviation of +/-3.3% : D/m(2) . s(-1) = 1.10 x 10(-6) exp[-1896/(T/K)].