ObjectiveWith the growing representation of older adults in the workforce, the health and fitness of older employees are critical to support active ageing policies. This systematic review aimed to characterise and evaluate the effects on physical activity (PA) and fitness outcomes of workplace PA interventions targeting older employees.DesignWe searched Medline, PreMedline, PsycInfo, CINAHL and the Cochrane Controlled Register of Trials (CENTRAL) for articles published from inception to 17 February 2020. Eligible studies were of any experimental design, included employees aged ≥50 years, had PA as an intervention component and reported PA-related outcomes.ResultsTitles and abstracts of 8168 records were screened, and 18 unique interventions were included (3309 participants). Twelve studies were randomised controlled trials (RCTs). Seven interventions targeted multiple risk factors (n=1640), involving screening for cardiovascular disease risk factors, but had a non-specific description of the PA intervention. Four interventions targeted nutrition and PA (n=1127), and seven (n=235) focused only on PA. Interventions overwhelmingly targeted aerobic PA, compared with only four interventions targeting strength and/or balance (n=106). No studies involved screening for falls/injury risk, and only two interventions targeted employees of low socioeconomic status. Computation of effect sizes (ESs) was only possible in a maximum of three RCTs per outcome. ESs were medium for PA behaviour (ES=0.25 95% CI −0.07 to 0.56), muscle strength (ES=0.27, 95% CI −0.26 to 0.80), cardiorespiratory fitness (ES=0.28, 95% CI −22 to 0.78), flexibility (ES=0.50, 95% CI −0.04 to 1.05) and balance (ES=0.74, 95% CI −0.21 to 1.69). Grading of Recommendations Assessment, Development and Evaluation criteria-rated quality of evidence was ‘low’ due to high risk of bias, imprecision and inconsistency.ConclusionsThe lack of high-quality effective workplace PA interventions contrasts the importance and urgency to improve the health and fitness in this population. Future interventions should incorporate strength and balance training and screening of falls/injury risk in multi risk factors approaches.PROSPERO registration numberCRD42018084863. (https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=84863).