The first data on faunistic composition of leaf beetles of 26 Agustos Nature Park, Afyonkarahisar, Turkey are presented. The field researches were conducted from April to November 2017. During this study, a total of 46 leaf beetles species belonging to 23 genera in 6 subfamilies were identified, all of which are recorded for the first time in the study area. Galerucinae was identified as the richest subfamily with 27 species. About 42.15% of the leaf beetle abundance was represented by three species of Alticini: Chaetocnema concinna (17.92%), Altica carduorum (13.01%) and Chaetocnema mannerheimi (11.22%). Eleven species were represented with only one or two specimens in the study area, and they were considered as rare taxa: Labidostomis cyanicornis, Clyptocephalus moraei, Leptinotarsa decemlineata, Aphthona pygmaea, Neocrepidodera ferruginea, Phyllotreta procera, Ph. vittula, Psylliodes circumdata, Ps. napi, Galeruca interrupta and Cassida seraphina (0.09%). In addition, short notes about host plant, phenology and abundance of each species are presented.