Three species of Telenomus Haliday are egg parasitoids of the hemlock looper, Lambdina fiscellaria (Guenée), in Canada. Telenomus coloradensis Crawford and Telenomus droozi Muesebeck are redescribed and Telenomus flavotibiaesp.nov. is described and illustrated from material collected in Quebec. Telenomus coloradensis was found to be the predominant egg parasite, followed by T. droozi. Telenomus flavotibiae was found to be an uncommon parasite of hemlock looper eggs. All three species are recorded from Newfoundland to British Columbia. Keys to species of Telenomus associated with the hemlock looper, including two closely related species previously confused in the literature, are also given.