Aims The aims of this study were to establish the uptake rate of seasonal influenza vaccine amongst oncology healthcare workers (HCWs) during the 2016/17 influenza season and to ascertain which factors were associated with or predicted vaccination, along with determining if national guidance regarding influenza vaccination for cancer patients is implemented. Methods A national cross-sectional study was carried out on clinical staff working in oncology day wards. Results Vaccine uptake during the 2016/17 season among oncology day ward staff was 48%. Fear of vaccine side-effects, believing that if one is healthy, there is no need for vaccination, and doubt about vaccine effectiveness negatively predicted vaccination. Most staff (87.6%) recommend vaccination to some or all patients. Conclusion Every effort should be made to ensure HCWs are given the opportunity to get vaccinated, provided with evidence of vaccine effectiveness and safety and empowered to recommend influenza vaccination to their patients.