Spatial segregation of the sexes in bryophytes has been implicated as the primary reason for the lack of sporophyte production in many dioicous bryophyte populations. Additionally, sex-specific microhabitat specialization by dioicous bryophytes may influence population sex ratios and the maintenance of sexually dimorphic traits. We examined habitat use of female and male M. inflexa in two populations in Trinidad and 10 populations in the U.S.A. to determine whether the sexes were spatially segregated within populations and if the sexes specialized on different microhabitats. Populations differed in habitat characteristics, sex ratios varied among populations, and populations consisted mainly of single-sex or non-sex-expressing patches of plants. Despite the fact that Marchantia inflexa is sexually dimorphic, female and male plants used areas of similar substrate, humidity, wind speed, and exposure within and among populations. In U.S.A. populations, males were found in areas with more open canopy and used a wider range of light environments than females. Although the sexes of M. inflexa were spatially separated within populations, they overlapped in habitat use and their distributions were not correlated with an environmental gradient.