Hopea hainanensis is one of the National Key Protected Plants in China and was classified as an Extremely Small Population (120 in total in the country) in 2012. It was also classified as a Critically Endangered Population by the International Union for Conservation of Nature (IUCN). The protection and restoration patterns of H. hainanensis populations has been the focus of local forestry work in Hainan Province since the 1960s. Traditional methods are mainly in-situ and ex-situ conservation, which have been used over 50 years but still have little effect on improving the original habitat of the population. Therefore, exploring effective population protection modes is of great significance to change this predicament. In this paper, we compared the development status of two Hopea hainanensis populations:the in-situ population from Bawangling Preserve and the ex-situ population in Fengmu Woodland, based on field investigations and statistical analysis. Our study revealed that the populations under both ex-situ and in-situ protections the growth type:young individuals made up the overwhelming majority, while middle-aged and elderly individuals were relatively few. Further, ex-situ protection population survival curves tended to be Deevey-I type, while the in-situ population survival curves tended to be Deevey-Ⅲ. Time-series prediction analysis showed that the ex-situ population of Maple had a certain recovery potential, while in-situ population regeneration of the Bawangling population was difficult to maintain and is, thus, facing decline. According to analysis results, habitat has a strong environmental screening effect on the I age individuals and thus resulted in seedling mortality rates up to 99.5%-meaning only 0.53% can transition to young tree stage. Despite high seedling mortality rates (90.3%) in ex-situ populations, 8.85% seedlings can transition to the young tree stage, demonstrating a more stable population. Therefore, Fengmu Woodland is a more suitable option for the survival of Hopea hainanensis populations. We suggest simulating the environmental conditions of ex-situ conservation in in-situ conservation areas to create a suitable environment to alleviate the endangered state of Hopea hainanensis populations in Hainan Province.