The digestive tracts of 50 working horses from private farms in Poland were examined. Thirty-seven nematode species, two tapeworm species and one species of botfly were recovered. The most prevalent small strongyle species were Cyathostomum catinatum, Cylicocyclus nassatus, Cylicostephanus goldi, Cylicostephanus longibursatus, Cyathostomum coronatum, Cylicostephanus calicatus, Cylicocyclus leptostomus and Cylicostephanus minutus. Thirteen cyathostome species showed a site preference in the ventral colon, five in the dorsal colon and three in the caecum. One species, Cylicocyclus triramosus, was new for Poland. Delafondia vulgaris was the most common large strongyle, with 74% prevalence, but low abundance. Parascaris equorum (26%) and Oxyuris equi (36%) were common. Strongyloides westeri (4%), Habronema majus (16%) and Habronema muscae (8%) were less prevalent. Both Habronema species were new for Poland. Tapeworm infection were not prevalent (Anoplocephala magna (4%) and Anoplocephala perfoliata (4%)). Botfly larvae were found in 40% of the horses examined. It was stated that no anthelmintics had been used on the farms.