Virulence of the wheat leaf rust populations of 1999 and 2000 from Slovakia was studied on Thatcher near-isogenic lines (NILs) with genes Lr1, Lr2a, Lr2b, Lr2c, Lr3a, Lr9, Lr10 (only in 2000), Lr11, Lr15, Lr17, Lr19, Lr21, Lr23, Lr24, Lr26 and Lr28. Seven pathotypes were determined from 36 rust samples in 1999, and 17 pathotypes from 45 rust samples in 2000. The frequency of virulence on Lr1, Lr2a and Lr2b was relatively low, and there was no virulence on Lr9, Lr19, Lr24 and Lr28. The frequency of virulence on Lr2c, Lr15, Lr23 and Lr26 varied between 53.0 and 97.8%. All isolates were virulent on Lr3, Lr11, Lr17 and Lr21. The identified pathotypes conformed with races 61SaBa, 57SaBa, 12SaBa, 6SaBa, 77SaBa, 6, 61 and 2SaBa. In 1999 races 61SaBa, 77SaBa and 57SaBa prevailed, in 2000 races 61SaBa, 57SaBa, 12SaBa, 6SaBa and 77SaBa were prevalent. Data on the reactions of 18 cultivars and advanced lines to six rust isolates of 2000 representing different pathotypes and to one isolate from the collection (race 14) are presented.