Wound healing is a complex process that involves several biological events, and a delay in this process may cause economic and social problems for the patient. The search continues for new alternative treatments to aid healing, including the use of herbal medicines. Members of the genus Caesalpinia are used in traditional medicine to treat wounds. The related species Poincianella pluviosa (DC.) L.P. Queiroz increases the cell viability of keratinocytes and fibroblasts and stimulates the proliferation of keratinocytes in vitro. The crude extract (CE) from bark of P. pluviosa was evaluated in the wound-healing process in vivo, to validate the traditional use and the in vitro activity. Standardized CE was incorporated into a gel and applied on cutaneous wounds (TCEG) and compared with the formulation without CE (Control) for 4, 7, 10, or 14 days of treatment. The effects of the CE on wound re-epithelialization; cell proliferation; permeation, using photoacoustic spectroscopy (PAS); and proteins, including vascular endothelial growth factor (VEGF), superoxide dismutase 2 (SOD-2) and cyclooxygenase 2 (COX-2) were evaluated. The TCEG stimulated the migration of keratinocytes at day 4 and proliferation on the following days, with a high concentration of cells in metaphase at 7 days. Type I collagen formed more rapidly in the TCEG. PAS showed that the CE had permeated through the skin. TCEG stimulated VEGF at day 4 and SOD-2 and COX-2 at day 7. The results suggest that the CE promoted the regulation of proteins and helped to accelerate the processes involved in healing, promoting early angiogenesis. This led to an increase in the re-epithelialized surface, with significant mitotic activity. Maturation of collagen fibers was also enhanced, which may affect the resistance of the extracellular matrix. PAS indicated a correlation between the rate of diffusion and biological events during the healing process. The CE from P. pluviosa appears promising as an aid in healing.