This study aimed to understand how functional traits change with elevation in a seasonal tropical forest. We collected leaf and wood samples from 15 dominant tree species at 880-1,010 m elevation and measured leaf area (LA), specific leaf area (SLA), leaf dry matter content (LDMC), leaf toughness (LTO), leaf thickness (LTH), and wood density (WD), and analyzed for changes in these traits with elevation at the species and community levels. We used the linear mixed model at the species level. At the community level, we analyzed the relationship between the community weighted mean (CWM) and elevation. At the species level, LA and SLA increased with elevation, while LDMC decreased, indicating intraspecific variation with elevation. No other traits correlated significantly with elevation. At the community level, CWMs were significantly correlated with elevation for all traits. The CWMs decreased with elevation, except for SLA, which increased with elevation. In addition, the values of CWMs with and without intraspecific variation were similar, suggesting that interspecific variation was more important for the CWMs. These results suggest that species with more conservative strategies for resource acquisition and use may dominate at lower elevations, where water stress is higher in the study site.