Cilacap has a high potential of marine fisheries. However, no scientific data is available on the potential of marine ornamental fish from that area. Here we reported the preliminary result of the potential of marine ornamental fish from south coast of Cilacap with special emphasize on species richness. A survey method with incidental sampling was conducted. Fish samples bought from the fish collector in Sentolokawat Village, District of South Cilacap at Cilacap City. The fish samples were collected in April, May, and July 2019. Taxonomic identification of the fish samples was referring to available reference and validated to the data in FishBase. Identification based on color pattern and meristic characters by considering geographic ranges of the specimen placed the samples into 28 species, 12 families, and three orders. Chaetodontidae was the most abundance family with nine species. Most fish belonged to Perciformes. We obtained lower number of species compared to the previous study for the south coast of Java. This could be due to that we collected samples from narrower areas and limited sampling periods. Nevertheless, our result provides information about the potential of marine ornamental fish in Cilacap as among promising income source for Cilacap Regency.  However, government intervention is absolutely necessary for sustainable used of ornamental fish in the area.

fish; marine; monsoon; ornamental; Cilacap