Abstract Background Interventions to promote physical activity among women breast cancer survivors (BCS) in low- to middle-income countries are limited. We assessed the acceptability and preliminary effectiveness of a theory-driven, group-based dance intervention for BCS delivered in Bogotá, Colombia. Methods We conducted a quasi-experimental study employing a mixed-methods approach to assess the 8-week, 3 times/week group dance intervention. The effect of the intervention on participants’ physical activity levels (measured by accelerometry), motivation to engage in physical activity, and quality of life were evaluated using generalized estimating equation analysis. The qualitative method included semi-structured interviews thematically analyzed to evaluate program acceptability. Results Sixty-four BCS were allocated to the intervention (n = 31) or the control groups (n = 33). In the intervention arm, 84% attended ≥ 60% of sessions. We found increases on average minutes of moderate-to-vigorous physical activity per day (intervention: +8.99 vs control: −3.7 min), and in ratings of motivation (intervention change score = 0.45, vs. control change score= −0.05). BCS reported improvements in perceived behavioral capabilities to be active, captured through the interviews. Conclusions The high attendance, behavioral changes, and successful delivery indicate the potential effectiveness, feasibility, and scalability of the intervention for BCS in Colombia. Trial registration ClinicalTrial.gov NCT05252780, registered on Dec 7th, 2021—retrospectively registered unique protocol ID: P20CA217199-9492018.