The giant blenny, Scartichthys gigas (Steindachner, 1876) (Blenniidae), is endemic to the eastern South Pacific and abundant in rocky intertidal environments. We investigated some ecological indices of the parasitefauna of 72 S. gigas acquired at Fishing Terminal from Chorrillos, Lima, Peru fromSeptember 2008 to August 2009. Fish were necropsied to census helminth and crustacean parasites. Four species of parasites were found with the following prevalence and mean abundance,respectively: an isopod, Ceratothoa gaudichaudii (H. Milne Edwards, 1840) (1.4% and 0.01), a copepod, Acanthocondria syciasis (Kroyer, 1863) (55.6 and 1.56), a digenean, Zoogonus rubellus (Olson, 1868) (26.4% and 0.26), a nematode, Johnstonmawsonia sp., (6.9 % and 0.17). Only linear correlation was observed between the size of host fish, and the prevalence and total abundance of Z. rubellus. Similarly, the size was fo...