ABSTRACT. – The goal of this study was to assess the impact of recreational harvesting on the populations of two sea urchin species, Paracentrotus lividus and Arbacia lixula, via their population densities and mean individual size at three sites in shallow water in the Gulf of Lion (NW Mediterranean Sea) characterised by different anthropogenic pressures. We observed a positive relationship between mean size and population density for P. lividus at one of the three sites. The increase in anthropogenic pressure was linked to a decrease of both population density and individual size. Differences in mean size and densities were detected for P. lividus between a site with high anthropogenic pressure and sites with moderate to low anthropogenic pressure. These results suggest the existence of an impact of recreational sea urchin harvesting on populations of P. lividus and A. lixula, and stress the necessity of a regulation of such practices, as their effects are likely to affect local ecosystems