Intoxication by ethylene glycol is the second most co-mmon cause of animal mortality, according to the Ameri-can Association of Poison Control Centers. Ethylene glycol is a product with low acute toxicity when acting through skin contact or if inhaled. But its toxicity is fully manifes-ted when it is ingested; it is indicated that the fatal dose of ethylene glycol is 4.4 ml/kg for dogs, 1.4 ml/kg for cats, 7-8 ml/kg for birds, and 2-10 ml/kg for bovine, with younger animals being more susceptible to such intoxica-tions. From our studies, we observed that this toxic substance has been identified in particular as the main to-xic agent in cats and dogs, having physical properties favourable to ingestion (slightly sweet taste, non-existent smell) and high toxicity. Ethylene glycol (antifreeze) into-xications, although they are not new, have recently star-ted to be more intentional than accidental, requiring the performance of medico-legal veterinary laboratory ex-pertise. As a result, the basis of this work is a number of 56 medico-legal laboratory veterinary examinations, res-pectively 34 dogs and 22 cats, in which we will present the macroscopic and microscopic aspects induced by this to-xic product in animals.