The rocky meso-littoral is an area characterized by the presence of an important amount of organisms that tolerate constant immersions. In this study the faunistic structure of an area of these features located on Concha Bay, Parque Nacional Natural Tayrona, Magadalena, Colombia, was evaluated. Samples from the west and east zones on this bay were taken. We found 19.912 specimens on the east and 11.198 on the west zones belonging to the Phyla: Cnidaria, Arthopoda, Equinoderma and Mollusca, being the last one the most frequent. However the diversity Index Shannon-Wiener indicates that the area studied has intermediate diversity values.