Objective: To investigate the effects of a short exercise intervention based on the use of a Zumba Fitness® programme on the quality of life (QoL) in inactive adult workers. Design: Non-experimental pre-test/post-test study involving one experimental group of inactive university workers. Setting: Riobamba in the Andean region of central Ecuador. Methods: A total of 60 inactive adults working at a university (age: 39 ± 1.0 years; 80% women, who used to perform < 150 min of moderate-vigorous physical activity per week) completed a 5-week Zumba Fitness® exercise intervention (three classes per week, 60 minutes per class; outside of work hours). QoL was assessed using the 36-Item Short Form Health Survey (SF-36) administered at baseline, post-intervention and 2 months after the intervention. Data were analysed using a per-protocol analysis. Results: The 5-week intervention improved six out of eight subscales of QoL, including general health (baseline: 63.6±2.51; post-intervention: 68.0±2.5; p = 0.007), physical role (baseline: 82.1±3.8; post-intervention: 90.6±3.3; p =0 0.029), emotional role (baseline: 71.3±5.0; post-intervention: 88.3±3.9; p = 0.001), social functioning (baseline: 76.9±2.6; post-intervention: 83.9 ± 2.6; p = 0.010), vitality (baseline: 60.4±2.8; post-intervention: 69.8±2.4; p < 0.001), mental health (baseline: 72.4±2.5; post-intervention: 80.4±2.3; p < 0.001) and the health transition perception item (baseline: 53.9±3.5; post-intervention: 63.6±3.1; p = 0.001). No statistical differences were found between post-intervention and 2-month follow-up; however, the majority of subscales which improved post-intervention (general health, emotional role, social functioning, vitality and mental health) were maintained at 2-month follow-up showing differences (p < 0.05) compared to baseline. Conclusion: A 5-week exercise intervention based on Zumba Fitness® programme could improve QoL in inactive adult workers and most improvements could be maintained at 2 months post-intervention.