This study addresses the longitudinal dispersive effect due to mass transport induced by progressive surface waves. Lagrangian drift is investigated to be the mechanism creating cross-sectional mean velocity variation, an essential component for Taylor dispersion. The dispersive effect is found to be more significant if the wave height is much larger thanwhereDis the diffusivity andTthe wave period. The longitudinal dispersion coefficient with a Stoke drift profile is first established. Subsequently drift profiles with viscous effect are considered and the dispersive effect increases substantially. The coupling of the oscillatory orbital motion of the pollutant particles under linear waves with background diffusion is further examined through a random walk numerical approach. Results show that, despite the possible modulation of the probability density with the wavy surface, the magnitude of the dispersion is not affected by the inclusion of the orbital motion.