Purpose The use of high-flow oxygen via nasal cannula has become increasingly more common in various patient populations given the multiple benefits for treating respiratory distress and failure. There is emerging, though varying research on the impact high-flow oxygen delivery may have on adult oropharyngeal swallowing function. The purpose of this literature review is to outline available research and examine study design, populations investigated, findings, and clinical considerations of these findings. Method After an extensive online database search, we found five available peer-reviewed research articles specifically investigating oropharyngeal swallowing function in adults receiving high-flow nasal cannula (HFNC) therapy. Each article was reviewed and summarized in detail with close attention paid to results and clinical implications. Limitations, indirectness, and/or methodologic flaws are highlighted for the readers' consideration. Conclusions Four prospective design studies and one retrospective data analysis collection have been published evaluating the effects of high-flow oxygen therapy on adult oropharyngeal swallowing. Three of the prospective design studies evaluated healthy adults; one prospective design and the retrospective analysis data collection investigated acute care patients requiring HFNC. Study findings varied greatly likely due to variability of each study's subject population, design, and methods. Variability of results may make it challenging for speech pathologists attempting to use evidence-based decision making in clinical practice. Additional studies investigating nonhealthy subjects undergoing instrumental swallow studies while on HFNC are warranted.