Chronic granulating wounds were established in rats by excising burns inoculated with Escherichia coli. Recombinant human basic fibroblast growth factor was applied at dosages of 1, 10, and 100 micrograms/cm2 to the wounds of three groups of 20 animals on days 5, 9, 12, 15, and 18 after injury. The rate of wound closure was compared with that of similarly wounded animals treated with saline vehicle alone. High levels of bacteria caused significant retardation of wound contraction. The addition of basic fibroblast growth factor at the 100 micrograms/cm2 dosage level markedly improved the rate of wound closure whereas inert vehicles applied alone were ineffective. Since bacterial counts did not decrease in the basic fibroblast growth factor treated wounds, basic fibroblast growth factor was not inherently bactericidal. Histologic examination of the wounds treated with basic fibroblast growth factor showed increased cellularity with increased numbers of fibroblasts and round cells. These results suggest basic fibroblast growth factor can overcome the defect in healing created by bacterial infection, and this peptide may have efficacy in the management of the contaminated wound.