This study aims to estimate the effect of Sericostachys scandens on the floristic composition of the development stages of woody species (regeneration, young tree, tree) in the Kibira National Park (PNK) in Burundi. The abundance of S. scandens and other woody species was measured in 100 plots of 50 m × 50 m and subjected to negative binomial regression and multivariate analysis of variance on a dissimilarity matrix (PermaNova). Liana density negatively affects regeneration (t = −10,170; p < 0.0001), young trees (t = −4.346; p < 0.0001), and trees (t = −7.740; p < 0.0001). Invasion by S. scandens leads to a variation in the floristic composition of young trees (p = 0.02) and trees (p = 0.01). Future studies should identify the species most at risk of local extirpation due to the proliferation of S. scandens in the PNK