Abstract: Differences in shell preference and utilization patterns among sympatric species of hermit crabs and between males and females of Pagurus lanuginosus were investigated. The shell utilization pattern of P. lanuginosus differed from those of three other species. While P. middendorffii and P. filholi crabs of≤3mm in shield length frequently occupied shells of Reticunassa fraterculus, comparably-sized P. lanuginosus did not. Most P. lanuginosus occupied shells of Chlorostoma lischkei and Homalopoma sangarense. The order of shell species preference was similar in both males and females of P. lanuginosus of>3mm in shield length; slight sexual differences were found in the shell preferences of smaller crabs. In shell size preference experiments, the relationships between crab size and size of chosen shell were similar between sexes for each shell species tested. The similarity in shell-size and-species preference and utilization patterns between males and females might be due to weak sexual selection for male body size.