This paper reports the yellowline arrow crab, Stenorhynchus seticornis, acting as cleaner of longjaw squirrelfish, Holocentrus adscencionis moray eels Gymnothorax funebris, G. moringa, G. vicinus and squirrelfish Holocentrus adscencionis at two reefs in the Baía de Todos os Santos, Bahia State, eastern Brazil. We believe that other species of reef fish are potential ‘clients’ of yellowline arrow crab and that this activity occurs throughout its distribution.