There have been few studies investigating the implications of the potential distribution of plant
invasions on native biodiversity due to climate change. In this study, we used combined climatic
suitability maps of 14 priority Invasive Alien Plant Species (IAPS) in Sri Lanka under the current
climate and under Representative Concentration Pathway (RCP) 4.5 and RCP 8.5 climate scenarios
for 2050 to examine the potential risks of plant invasions on native plant biodiversity. We used
three types of layers defining plant biodiversity patterns for Sri Lanka; (i) nine zones of plant
endemism (zones of high floristic richness and endemicity), (ii) eleven threatened endemic taxa
and (iii) eight forest-related ecosystems. Our results reveal that the biodiversity-rich zones of
endemism are at potentially high-risk under climate change. The potential risks on threatened
endemic plants are likely to reduce slightly under an RCP 4.5 low-emissions scenario and be
intensified under an RCP 8.5 high-emissions scenario. Forest-related ecosystems are vulnerable
to IAPS to varying degrees; dry zone ecosystems are predicted to increase the risks of IAPS, while
those in the wet zone are envisioned to decrease. Overall, our findings suggest that the potential
risks of plant invasions on native plant biodiversity differ significantly under projected climate
change. Greater understanding of the potential risks of IAPS at an early stage is important in
prioritising future conservation measures for effective protection of native biodiversity.