Ten pools and ponds were monitored on a weekly basis for presence of mosquito pathogens and parasites over a three year period near Edmonton, Alberta. Acari, fungi, Microsporidia and Peritrichida were found associated with mosquitoes. Percentage of collections with pathogens and parasites (prevalence) followed by the mean percentage infection within the samples, in parentheses (estimated % incidence) for the three year period were as follows: Coelomomyces psorophorae var. psorophorae 0.9(0.01-0.02), Culicinomyces clavisporus 1.2(0.09-0.2), Saprolegniales 50.1(15), Smittium sp. 23.0(4), Microsporidia 10.9(0.6-1.4), Peritrichida 43.4(30) and Acari 3.2(0.04). The high incidence of Saprolegniales may be a result of attack on stressed individuals under laboratory conditions. Several host and country records are reported. It is concluded that pathogens and parasites generally had little effect on the mosquito populations.