Exploring the effects of habitat heterogeneity at different scales on bird communities is crucial for conservation practices. This study conducted four seasonal surveys of bird communities in the Tianma National Nature Reserve, Anhui Province, in 2023, and tested the effects of multi-scale habitat heterogeneity and related environmental factors on bird community structure and α and β diversity. A total of 14,593 birds were recorded in the field, which belonged to 10 orders, 37 families, and 126 species, including 20 nationally protected species and 3 species classified as Vulnerable (VU) by the IUCN. The number of individuals, number of species, and Shannon-Wiener diversity index of birds were positively correlated with the 100 m habitat heterogeneity index, whereas the number of individuals and species exhibited a negative correlation with distance from the main road. The number of bird species feeding on invertebrates increased with the 500 m habitat heterogeneity index, while the number of bird species feeding on vertebrates, fish and carrion exhibited a decrease with the same index. Conversely, the number of bird species feeding on vertebrates, fish and carrion demonstrated an increase with the 100 m building area index. The number of individuals of bird species feeding on plants and seeds, bird species feeding on fruits and nectar, and omnivorous birds exhibited an increase with the 100 m habitat heterogeneity index, while the number of individuals of bird species feeding on fruits and nectar and omnivorous birds demonstrated a rise with the 500 m water body area ratio. The number of bird species feeding on fruits and nectar and omnivorous birds exhibited an increase with the proportion of 500 m water body area and a decrease with distance from the main road. Different feeding guilds of birds showed varying responses to habitat heterogeneity. The overall β diversity was predominantly characterised by the turnover component. Pairwise β diversity increased with differences in the 100 m habitat heterogeneity index, the 500 m habitat heterogeneity index, and the distance from the main habitation, as well as with differences in the percentage of 100 m building area. The turnover component increased with differences in the 100 m habitat heterogeneity index, elevation, and distance from the main habitation. Additionally, the nested component increased. The nested component increased with differences in the 100 m habitat heterogeneity index, the 500 m habitat heterogeneity index and distance from the main habitation. These results indicate that the bird community in the Tianma National Nature Reserve is mainly influenced by habitat heterogeneity at different scales. It is recommended to increase habitat heterogeneity to better protect the bird diversity.