Tetecho (Neobuxbaumia tetetzo, Coulter, Backeberg) is an endemic columnar cactus in Zapotitlán Salinas Valley, Puebla, Mexico. Tetecho has an important role in the semi-arid ecosystem. For at least 8 years, tetecho cactus has shown symptoms of soft rot and necrosis. Insects were associated with the diseased plants. The main goal of the research was to identify insects associated with diseased tetecho and verify if they carry the pathogen. Insects were collected from 80 tetecho plants that showed typical symptoms. The insects were identified using taxonomic keys; bacteria in the intestine of the insects were identified by direct sequencing of IGS 16S-23S rDNA, gyrB, and rpoB genes. The insects and their frequency were larvae of Lagocheirus lugubris Dillon (Coleoptera: Cerambycidae) in 100% of the samples; larvae and adults of Chalcolepidius sp. Eschscholtz (Coleoptera: Elateridae) in 20%; and adults of Glyphidops flavifrons (Bigot) (Diptera: Neriidae) in 70% of the samples. Pseudomonas Migula was isolated from the intestine of larvae and adults of L. lugubris and G. flavifrons. Carnobacterium Collins et al. and Curtobacterium Yamada & Komagata were isolated from larvae of L. lugubris; Pectobacterium carotovorum subsp. brasiliense Nabhan et al. was inside larvae and adults of L. lugrubris and adults of G. flavifrons.