Introduction and hypothesis: Most synthetic meshes used in transvaginal surgery are made of polypropylene, which has a stable performance, but does not easily degrade in vivo. However, mesh-related complications are difficult to address and have raised serious concerns. A new biomaterial mesh with good tissue integration and few mesh-related complications is needed. To evaluate the effect of a new bacterial cellulose (BC) mesh on pelvic floor reconstruction following implantation in the vagina of sheep after 1 and 12?weeks. Methods: The meshes were implanted in the submucosa of the posterior vagina wall of sheep. At 1 and 12?weeks after surgery, mesh–tissue complex (MTC) specimens were harvested for histological studies and biomechanical evaluation. At 12?weeks after surgery, MTC specimens were biomechanically assessed by a uniaxial tension “pulley system”. Results: The BC mesh elicited a higher inflammatory response than Gynemesh?PS at both 1 and 12?weeks after implantation. Twelve weeks after implantation, the BC mesh resulted in less fibrosis than Gynemesh?PS. Compared with the Gynemesh?PS group, the BC mesh group had increased mRNA expression of MMP-1, MMP-2, and MMP-9 (P < 0.05), but decreased expression of the anti-inflammatory factor IL-4 (P < 0.05). Twelve weeks after implantation, the ultimate load and maximum elongation percentage of the BC mesh were significantly lower than those of Gynemesh?PS. Conclusions: The BC mesh could not be a promising biomaterial for pelvic floor reconstructive surgery unless the production process and parameters were improved. ? 2019, The International Urogynecological Association.