A total of 250 Merino lambs from the Lubuskie province and 83 Suffolk lambs from the Zachodniopomorskie province were examined. The level of infection with Eimeria protozoa was determined on coproscopic examinations using the Willis-Schlaaf flotation method. The species composition of the coccidia was determined using Pellerdi's system. The prevalence of lamb infection with coccidia averaged 85.18% in the Zachodniopomorskie province and 55.32% in the Lubuskie province. Coproscopic examinations showed that the animals were infected with different species. Eight species were isolated from faecal samples: E. faurei, E. ovinoidalis, E. pallida, E. intricata, E. parva, E. arloingi, E. ninakohlyakimovae and E. granulosa. E. parva (53%) and E. ninakohlyakimovae (47.8%) were the dominant in the Zachodniopomorskie province, and E. ninakohlyakimovae (65%) and E. intricata (43.3%) in the Lubuskie province.