In 1990 leaf rust of wheat (Triticum aestivum) caused by Puccinia recondita f. sp. tritici was first observed on June 21 in southern Manitoba. Infection severity ranged from 20 to 100% in susceptible trap plots; however, commercial cultivars had sufficient resistance and yield losses were minimal in these wheats. A total of 37 virulence phenotypes of the fungus in Canada were detected using 15 isogenic Thatcher lines as differentials. The most common phenotypes were PBL-B in Ontario and Quebec; MDB-14a, MFB-14a, and TBG-14a in the prairies, and NBB-B,18 in British Columbia. No major changes in the identity and prevalence of P. recondita virulence phenotypes in Canada occurred between 1989 and 1990.