After a case of Angiostrongylus vasorum (canine lungworm) was diagnosed in the province of Chieti (Italy) in early 2008, parasitological research was conducted to investigate the presence of the parasite in dogs in the area. A total of 178 dogs, 56 carcasses and 122 stool samples were examined between January and September 2008. The carcasses were examined for the presence of adult parasites in the right ventricle and pulmonary artery, and larval forms in the internal organ and brain tissues. The faeces were inspected for larval form L1 using three diagnostic methods that are currently used to test for endoparasites and larvae of bronchopulmonary strongyles. A total of 20 cases of canine angiostrongylosis were diagnosed (8.9%), with adult parasites being identified in 5 dogs, and L1 larvae in another 15. The anatomo-pathological examination of the carcasses of the dogs infested with adult nematodes revealed pneumonia, pleurisy, reddish foam in the trachea, effusion of serohaemorrhagic fluid in the thoracic cavity and enlarged mediastinic and mesenteric lymph nodes. Histological examination of the tissues showed serious, similar syndromes with lesions caused by colonisation of the kidneys, lymph nodes and brain by the parasites. Given the large number of cases confirmed in relation to the period of study (9 months), it is essential to include angiostrongylosis among the differential diagnoses made in clinical and post-mortem examinations of dogs in the province of Chieti and in the neighbouring areas.