Wheat stripe rust caused by f. sp. ( ) poses a great threat to wheat production worldwide. The rapid change in virulence of leads to a loss of resistance in currently resistant wheat cultivars, which results in frequent disease epidemics. Therefore, a major focus is currently placed on investigating the molecular mechanisms underlying this rapid variation of pathogenicity and coevolving wheat resistance. Limited by the lack of a system for stable transformation of and the difficulties in wheat transformation, it is not easy to generate deeper insights into the wheat- interaction using established genetic methods. Nevertheless, considerable effort has been made to unravel the wheat- interaction and significant progress is being made. Histology and cytology have revealed basic details of infection strategies and defense responses during wheat- interactions, identified cellular components involved in wheat- interactions, and have helped to elucidate their role in the infection process or in plant defense responses. Transcriptome and genome sequencing has revealed the molecular features and dynamics of the wheat- pathosystem. Extensive molecular analyses have led to the identification of major components in the wheat resistance response and in virulence. Studies of wheat- interactions have now entered a new phase in which cellular and molecular approaches are being used. This review focuses on the cellular biology of wheat- interactions and integrates the emerging data from molecular analyses with the histocytological observations.