Diplopods (millipedes) are one of the important groups of terrestrial Arthropoda in tropical forest ecosystems. Despite their ecological importance, data on millipede populations are still scarce and outdated in Cameroon. The first comparative eco-faunistic analysis is presented of two local populations of Diplopoda in two lowland rainforests (nearly primary and secondary) during 12 months (2015 2016) at the southern periphery of the Campo Ma'an National Park in southern Cameroon. The millipedes were collected using pitfall trapping and quadrat sampling, their diversity and distribution analyzed with the help of two diversity indexes and two nonparametric estimators. Overall, 27 species in eighteen genera, ten families and four orders were revealed in the two forests, yet each faunule was about equally rich (23 and 22 species in the primary and secondary forest, respectively) and peculiar (five and four species unique, respectively). The Odontopygidae was the most abundant family, which made up to 33% of the total species diversity. The most abundant species in both forests was Aporodesmus gabonicus (26.8% of occurrences). This study shows that despite the similarity in millipede species richness between both habitats, the species composition of all habitats was different. Some species occurred in two habitats whilst others were restricted to only one habitat.