This study documents the diversity and distribution of the subfamily Attageninae (Coleoptera: Dermestidae) in Saudi Arabia based on the examination of specimens from institutional and private collections, and field surveys using different trapping and collection methods. It enumerates 20 species belonging to two genera, Attagenus (19 species) and Telopes (one species). Six species are newly recorded for the country: Attagenus barbieri Pic, 1946; A. jakli Háva, 2021; A. kadleci Háva, 2012; A. vanharteni Háva, 2009; A. yemensis Háva & Herrmann, 2014; and Telopes tessellatus Reitter, 1887. Morphological examinations led to the exclusion of five previously misidentified species from the Saudi fauna: A. dichrous Roth, 1851; A. fasciolatus (Solsky, 1876); A. heydeni (Reitter, 1881); Telopes obtusus (Gyllenhal in Schönherr, 1808); and Telopes reitteri (Mroczkowski, 1968). The distribution of Attageninae reveals the influence of environmental gradients on species richness, with mid-altitude areas (601–1500 m) serving as biodiversity hotspots, hosting 14 species. Lowland and highland specialists display niche adaptation, with species like A. apicalis and A. logunovi restricted to low altitudes (≤ 600 m) and A. kadleci found exclusively in high-altitude environments (> 2000 m). Approximately 40% of the Attageninae species in Saudi Arabia are found within protected areas. This study identifies five endemic species in the Arabian Peninsula, including one exclusive to Saudi Arabia (A. logunovi). These findings increase the number of known attagenine species by 43% in Saudi Arabia and 7% in the Arabian Peninsula, highlighting the need for systematic surveys and taxonomic revisions to reveal the overlooked biodiversity in the region.