¹Department of Internal Medicine, Faculty of Veterinary Medicine, University of Ondokuz Mayis, TR-552 00 Kurupelit, Samsun - TURKEY DOI : 10.9775/kvfd.2018.20817 Direct contact with the Pine Processionary Caterpillar (PPC) Thaumetopoea species induces severe local allergic and toxic reactions both in man, dogs even in cats in Mediterranean countries, with the necessitate of medical intervention. Caterpillars are the larvae of these insects look like hairy and colored orange-brown with blue bands, have covering of irritant hairs which called as setae; along its whole body except ventral surface [1]. These chitinous spines are rich in thaumetopoein, which makes them an urticating protein [2]. Furthermore, setae of the caterpillar could also keep their potential toxicity in the left nests after chitin changing period [3]. The aim of the present case report is to define first clinical manifestation of an acute erosive gastritis due to PPC setae ingestion in a four months old, male Pembroke Welsh Corgi. Keywords : Acute Erosive Gastritis, Caterpillar Setae