Laminaran, a polysaccharide extracted from marine algae, exhibits attractive properties being non-toxic, hydrophilic and biodegradable. The aim of this study was to investigate the effectiveness of a cream based on the brown seaweed Cystoseira barbata laminaran (CBL) for healing full thickness wounds induced on rats. The antibacterial activity of CBL was evaluated against Gram positive and Gram negative bacteria and the antioxidant properties were assessed using five different assays. To highlight the healing effectiveness of CBL-based cream, the response to treatment was assessed by macroscopic, histologic and biochemical parameters and was compared to controls. CBL, recovered (7.27%) by ultrafiltration (1-10 kDa) and predominantly consisted of (1 -> 3)-linked beta-D-glucopyranose residues with a small level of (1 -> 6)-glycosidic bonds, showed noticeable antioxidant and antibacterial properties. The cream containing CBL as an active ingredient exerted a promoting healing effect. The wound contraction reached 98.57 +/- 1.31% after thirteen days of treatment. The derma in CBL treated group is properly arranged and revealed an improved collagen deposition and an increased fibroblast and vascular densities compared with the control groups. Overall, these results established, for the first time, a scientific in vivo evidence of the efficiency of CBL as a wound healing agent of interest in modem medicine.