Shift workers are at increased risk of a range of chronic diseases and there is evidence to suggest that these risks can be ameliorated by physical activity. Little is known however about the efficacy of physical activity interventions in shift workers. The aim was therefore to critically review the literature to improve understanding of the efficacy of physical activity promotion initiatives for this occupational group. A systematic review of randomized controlled trials of physical activity in shift workers was conducted in 2016–2017 following the Preferred Reported Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Only seven studies were found. None of the studies measured changes in physical activity behaviour or reported on the timing or setting of the intervention protocols. Instead, most focused on health-related outcomes including body composition, fitness and sleep. Almost all provided physical activity ‘prescriptions’ with walking or ‘aerobic activity’ as the primary intervention mode and most reported significant improvements in one of the outcome measures. Although the findings suggest that physical activity may mitigate intermediate risk factors associated with non-communicable diseases (NCD) in shift workers, the studies offer little insight into physical activity behaviour change in this occupational group. Future research should assess actual changes in physical activity behaviour, and its determinants, as well as the reach and uptake of intervention strategies in this challenging population group.