Background. Wound healing is a dynamic process that could be accelerated by growth factors. We investigated the effect of recombinant bovine basic fibroblast growth factor (rbFGF) on burn healing in a randomised placebo-controlled trial. Methods. We recruited 600 patients with superficial or deep second-degree burns. Patients received 150 AU/cm² daily topical rbFGF (n = 300) or placebo (n = 300) plus vehicle. We assessed healing by photography, punch-biopsy, and clinical examination. Findings. All patients treated with rbFGF had faster granulation tissue formation and epidermal regeneration than those in the placebo group. Superficial and deep second-degree burns treated with rbFGF healed in a mean of 9.9 (SD 2.5) days and 17.0 (4.6) days, respectively, compared with 12.4 (2.7) and 21.2 (4.9) days (p = 0.0008 and p = 0.0003, respectively). No adverse effects were seen locally or systemically with rbFGF. Interpretation. rbFGF effectively decreased healing time and improved healing quality. Clinical benefits would be shorter hospital stays and the patient's skin quickly becoming available for harvesting and grafting.