Pine processionary, Thaumetopoea pityocampa Denis and Schiffermüller, 1775 is a moth that belongs to the order of insects Lepidoptera, and family Notodontidae. The larvae of pine processionary moth are the main pest of pines all over the world, but mainly in Mediterranean region. The contact with pine processionary caterpillar (lepidopterism) can produce a strong inflammatory reaction on skin and mucous membranes. Other findings include hyperthermia, tachypnoea, respiratory distress, cyanosis and tongue oedema, labial angioedema, ptyalism, bilateral submandibular lymphadenomegaly, conjunctivitis and severe tongue necrosis. Tough, few veterinary cases have been published. Also in Poland pine processionary moth (Thaumetopoea pinivora) is present, especially near the Baltic coast and can be a possible health risk for both humans and animals (especially dogs). The aim of this article is to increase knowledge about the clinical manifestations of pine processionary caterpillar contact, which may be useful for diagnosis of this dangerous disease.