The amber sites from the Chiapas Highlands in southwestern Mexico constitute an Oligo-Miocene Amber-Lagerstätte (ca. 24 Ma) whose mines and pits at Simojovel, Totolapa, and Estrella de Belén yield exceptionally preserved fossil inclusions, notably insects from an estuarine wetland. A comprehensive cross-referenced catalog of insects and their close relatives (Arthropoda: Hexapoda) recorded in Mexican amber has been compiled. The catalog comprises 589 fossil records, including 21 orders, 180 families, 230 genera, and 193 species. Data show the fossil diversity of insects based on 65 years of taxonomic descriptions. The catalog also consists of an online database for consultation and permanent updating. Accordingly, the taxonomic composition of Hexapoda in Oligo-Miocene Mexican amber is a significant addition to the current knowledge of the diversity of Lagerstätte taxa distributed worldwide.