<p>Biological invasions significantly impact biodiversity by altering ecosystem attributes, potentially leading to species loss and environmental homogenization. These changes reduce habitat heterogeneity, decreasing food availability, shelter, and nesting sites, ultimately affecting bird diversity, making birds particularly sensitive to structural habitat modifications caused by invasive plants. However, the effects of invasive plants on bird diversity remain unclear due to inconsistencies across studies. Here, we conducted a global meta-analysis to quantify the magnitude and direction of the impact of invasive plants on bird diversity. We also assessed how invasive species traits and history of disturbance influence bird responses. We showed that invasive plants reduce both bird richness and bird abundance. Furthermore, species traits, particularly dispersal syndrome and growth habit, strongly influenced bird responses to invasion. Plants with a non-endozoochoric dispersal syndrome had a stronger negative impact, reducing both richness and abundance. Similarly, herbaceous invasive plants had the most pronounced negative effect, decreasing bird diversity. Furthermore, bird communities in historically disturbed areas were less affected by plant invasions compared to those in undisturbed areas. These findings highlight the overall negative impact of invasive plants on bird communities, with the magnitude of the effect depending on biological traits of the invasive plants and the disturbance history of the invaded habitat.</p>