The term 'presenteeism' is a relatively new concept in workplace health, and has come to signify being at work despite poor health and performing below par. Presenteeism, which is potentially critical to employers, has been associated with a range of psychosocial outcome measures, such as poor mental health and employee well-being. Physical activity is a potential strategy for reducing presenteeism, and for improving the mental health of employees. This article reviews evidence on the relationships between physical activity and employee well-being and presenteeism in the workplace, and identifies directions for research in an emerging field. Electronic and manual literature searches were used to identify 20 articles that met the inclusion criteria. These included 13 intervention trials (8 randomized controlled trials, 5 comparison trials) and 7 observational studies (3 cohort, 4 cross-sectional). Outcome measures were grouped into 'workplace well-being', 'psychosocial well-being' and 'physical well-being'. Studies measured a wide variety of outcomes, with absenteeism being the most commonly assessed. Evidence indicated a positive association between physical activity and psychosocial health in employees, particularly for quality of life and emotional well-being. However, findings were inconclusive as to the role of physical activity in promoting workplace well-being. Only one study reported on presenteeism, with mixed evidence for outcomes. This article indicates that physical activity and employee psychosocial health are positively related, but there is limited evidence of a relationship between physical activity and presenteeism. A standardized definition of presenteeism and an appropriate evaluation tool are key research priorities if the complex relationships between physical activity and workplace well-being are to be better understood.