Gaeumannomyces graminis is an etiologic agent of take-all, economically important disease of cereals worldwide. A polymerase chain reaction with variety-specific primers was successfully used for detection of G. graminis var. tritici in plant tissue. Obtained results showed that this diagnostic method is a very sensitive and useful tool for detection of the pathogen even before disease symptoms arise. DNA polymorphism revealed by RAPD-PCR with three arbitrary primers was suitable for assessing genetic variation among Ggt isolates originating from wheat and rye.