The aim of this study was to investigate the actual and the potential role of the primary care nurse (PCN) in the prevention of cancer. International studies have indicated that a range of strategies can have an impact on the incidence of cancer. Due to their frequent front-line contact with the public, PCNs can play an important role in the primary prevention of cancer. Nonetheless, there is a lack of information on their actual and potential role in cancer prevention. A sequential confirmatory mixed methods approach was used. Postal questionnaires were administered to PCNs [n = 500; 225 returns (response rate 45%)] followed by semi-structured interviews (n = 15). PCNs provided high levels of cancer prevention activities, specifically focusing on smoking cessation, obesity and cervical screening. They considered that their cancer prevention role could be improved through additional practice-based training and more collaborative inter-professional working. They also identified the need for a better understanding of how to change people's attitudes and behaviours regarding cancer prevention. Evidence from this study provide important insights into the potential of the PCN to empower individuals to take responsibility for their own health and make more informed lifestyle choices.