Dasyurid marsupials are the dominant carnivore-insectivores of Australia and New Guinea, and they inhabit all major ecosystems types in both regions. My study focused on five dasyurid species within the genus Murexia that are endemic to New Guinea. The five species are: Murexia longicaudata, M. rothschildi, M. habbema, M. naso, and M. melanurus. Phylogenetic and phylogeographic studies were conducted to test species boundaries, assess intraspecific relationships within species, and determine whether genealogical relationships among populations corresponded to geographical separations. Maximum parsimony, additive distance, and maximum likelihood analyses were performed in order to verify accuracy and robustness of results. I obtained a concatenated tree using six genes for the phylogenetic analysis, which recovered the monophyly of the genus Murexia with a strong bootstrap support (100%). The phylogeographic portion of this study, using the mitochondrial control region, showed sound genetic variation among populations of Murexia.