Chemical studies on the constituents of Dracaena cochinchinensis led to the discovery of eight new flavonoid derivatives (1–8) along with 14 known compounds (9–22). The identification and structural elucidation of these isolates were based on spectral analyses. All isolates were tested for antibacterial activities against Helicobacter pylori (ATCC43504) and thrombin inhibitory effects. As a result, new flavonoid derivatives 6 and 7 and (2S)-4′,7-dihydroxy-8-methylflavan (11) were found to be most efficacious against H. pylori (ATCC43504) with MIC values of 29.5, 29.5, and 31.3 µM, respectively, and the seven new flavonoid derivatives (1–7) and one known biflavonoid (9) were observed to exhibit moderate thrombin inhibitory activity.