To explore the factors explaining butterfly diversity in a landscape mosaic of different habitats, we conducted a series of field surveys in the Saihawla National Nature Reserve. This reserve comprised of seven habitats: typical grassland, wetland, mountain valley meadow, degraded grassland, farmland, mountain xerophytic shrub and mountainous shrub. From May to September 2017, we recorded a total of 2,290 butterfly individuals belonging to 63 species, 42 genera, and 5 families. Nymphalidae, with the most species (34) and the most individuals (991), was the dominant family in the reserve. Five species dominated the community: Papilio Xuthus, Pontia daplidice, Aporia crataegi, Aglais urticae, Speyeria aglaja. The species-abundance analysis showed a normal distribution model, suggesting a relatively stable community with the range of butterfly activity extending to different habitats due to the continuity of vegetation types. However, we also found that butterfly distribution in Saihanwula was closely related to the distribution and composition of vegetation among habitats. The Mountainous shrub had the highest biodiversity index and the lowest dominance index, whereas degraded grassland had the lowest biodiversity index and species richness, but the highest dominance index. The Mountain valley meadow had the most number of families, genera, species, and individuals, the degraded grassland had the lowest number of families, genera, species, and individuals. Faunal distribution analysis show that widely distributed species occupied 63.49% and Palaearctic species occupied 36.51%. Furthermore, butterfly diversity in the different habitats of the reserve varied significantly between months. Finally, we found that numbers of butterfly individuals and species increased with higher temperatures, while rainfall had no significant correlation. In conclusion, We believe that appropriate interference is conducive to the development of butterfly diversity, strong human disturbance seriously destroyed grassland environment, affected butterfly survival and reproduction, and reduced butterfly diversity.