Fire is a major type of disturbance that affects forest structure, species diversity, and species composition. In western Madagascar, where seasonally dry forests dominate, recurrent anthropogenic fires—primarily from slash-and-burn agriculture—threaten forest resilience. However, few studies have examined the effects of recurring fires on vegetation. We examined how recurrent fires affected forest structure and species composition in Ankarafantsika National Park, NW Madagascar. We selected three adjacent areas with contrasting burn histories in ANP: Once-Burned (2021), Twice-Burned (2017 and 2021), and Not-Burned (no recorded fire history). In each, we established 21 systematically placed 5m by 5 m plots, recording all woody stems with DBH ≥ 1 cm for species identity and size. We also assessed ground conditions at 13 points per plot, recording bare ground, dead wood, charcoal, ash, and litter depth. We compared DBH distribution, stem density, species richness, diversity indices, and community composition among the three areas. Compared to the Not-Burned area, repeated fires resulted in declines in stem density, tree species richness, and Shannon diversity. NMDS and cluster analyses showed major shifts in species composition between Once-Burned and Twice-Burned areas. Of the 107 species detected across Once-Burned plots, 76 species and 41 species were shared with Once-Burned and Twice-Burne plots of comparable areas, respectively. Evergreen species dominated across all fire histories; however, deciduous species were slightly more abundant in Twice-Burned areas, suggesting shifts of community composition towards pioneer species including shrubs and lianas. Twice-Burned areas had more bare ground, charcoal, and grasses, indicating a long-term shift of various ecosystem properties. These results suggest that repeated fires alter forest structure and reduce species diversity, emphasizing the need for targeted fire management in ANP to mitigate the loss of native species and support forest resilience.