The present article is a corpus-based descriptive/comparative study of lexical bundles (LBs) in two university genres: textbooks (TBs) and research articles (RAs) on applied linguistics. It aims to identify the LBs used in the two genres, compare them on the basis of their functional type and frequency and explore how they are related to genre. To this end, four-word LBs were identified in two corpora drawn from applied linguistics TBs and RAs. The comparative analysis revealed that there are interesting differences between the two genres in terms of discourse functions: the occurrence of LBs in the TBs was lower than in the RAs; attitudinal/modality LBs occurred more frequently in the TBs than in the RAs; epistemic LBs occurred more frequently in the RAs than in the TBs; discourse organizers occurred more frequently in the RAs than in the TBs; and time, place and text reference LBs occurred almost twice as frequently in the RAs. The findings build on research into the variations of genres in terms of the use and functions of LBs in discipline-specific corpora.