Few cases of infection with Paramphistomum spp. have been reported from cattle in Canada. During the course of a recent study of bovine fascioliasis both P. microbothrioides and P. liorchis were found in the rumen of dairy cattle slaughtered in a Quebec abattoir. Eggs in feces were distinguished on the basis of their size. Coprological analysis of 932 samples from 601 cows on 17 selected farms in Portneuf County (Quebec) revealed that 34% of the animals were infected with P. microbothrioides and 1% with P. liorchis. Based on data from one herd there appears to be significant seasonal variation in egg passage for P. microbothrioides. Furthermore, old cows exhibited a higher prevalence of infection.