The first clinical case of canine angiostrongylosis from Slovakia, previously infection-free country, is described. 18-month old male Bernese mountain dog living in south-eastern part of Slovakia showed poor health condition characterized by weight loss, irritating cough, dispnoe, intense salivation, vomiting and bilateral scleral bleeding. Two times even the acute physical collapse occurred. Blood analysis was provided and revealed increase of total protein, eosinophilia, monocytosis, and mild thrombocytopenia. Anaemia characterized by reduced number of erythrocytes and reduced levels of haemoglobin, packed cell volume and iron was also diagnosed. Larvoscopic Baermann technique revealed the presence of Angiostrongylus first stage larvae. Infected dog excreted larvae in high numbers — in 10 g of the faecal material more than 800 larvae were counted. DNA analysis using PCR confirmed the presence of Angiostrongylus vasorum species. The first clinical case of angiostrongylosis has evidenced that the new life-threatening parasitic disease of dogs has spread to the territory of Slovakia. A serious effort is therefore inevitable to increase the professional awareness and knowledge on diagnosis, treatment and prevention.