Animals exhibit a range of dispersal strategies that impact on the organisation of individuals and can be influenced by both the environment and population demography. We examined the fine-scale spatial genetic structure and patterns of relatedness in 139 adult eastern grey kangaroos (Macropus giganteus) to test predictions of male-biased dispersal and female philopatry in comparison with previous studies in different environments in the species’ distributions. We found evidence of limited differences between the sexes, with little spatial genetic structure in both males and females. The levels of relatedness among females in close proximity were not indicative of close relatives (e.g. mother–daughter) and there was no evidence of matrilineal structure. Among males, there was little evidence of genetic structure. Although our results are, in general, consistent with those of previous studies, we found study-specific differences in the extent of genetic structure that appear to be related to differences in environmental and demographic conditions across the distribution. This highlights the need for additional research focussing on populations from a range of environmental conditions.