Previous research has identified the importance of promoting behaviour change within the offshore workforce. This qualitative study sought to: identify self-care behaviours perceived to require behaviour change within the offshore workforce, and explore perceived potential behavioural determinants.This study included the perspectives of both offshore workers (OWs, n = 16) and healthcare practitioners (HCPs, n = 12) from the global workforce. Telephone interviews were conducted, recorded electronically and transcribed. Transcripts were analysed independently by two researchers using a Framework Approach and the Theoretical Domains Framework (TDF) to support coding.Healthy eating and alcohol intake were behaviours perceived by OWs and HCPs to require change within the offshore workforce. Knowledge (e.g. availability of nutritional knowledge), intentions (e.g. role of motivation), memory, attention and decision process (e.g. effect of boredom), environmental context and resources (e.g. influence of environmental stressors), social influences (e.g. influence of others), emotion (e.g. influence of emotional state) and behavioural regulation (e.g. influence of willpower). TDF domains were reported by both OWs and HCPs in relation to OWs' healthy eating and physical activity behaviours.The determinants identified as mechanisms of behaviour may be targeted in future interventions which aim to promote engagement in self-care within the offshore workforce.