Biodiversity baselines were established for dragonflies (Insecta: Odonata) of Bukit Timah Nature Reserve, Singapore, based on quantitative and qualitative samplings. Surveys were conducted from December 2014 to February 2016. Hydrological, physicochemical parameters and habitats were analysed to understand the main drivers structuring the dragonfly community. A total of 829 odonate specimens were recorded during the quantitative sampling, comprising 36 species of 28 genera in 11 families. The species diversity in each of the six sampling sites was compared using the Shannon-Wiener Index (H'). Hierarchical clustering and Detrended Correspondence Analysis (DCA) indicated that three main groupings of sites existed, each with a distinct community of associated species. Further analysis by Non-metric multidimensional scaling (NMDS) on the relevant distance based on species composition at the six sampling sites, together with 21 environmental variables showed that these groups were significantly associated with respective environmental variables. An updated species list of Bukit Timah dragonflies is provided for future reference, with 55 species of 43 genera in 12 families. Disturbance and threats to the odonate fauna of the Bukit Timah Nature Reserve are identified and conservation management measures are discussed.