Biopolymer blends between bacterial cellulose and alginate have good potentials for production of biomedical materials. The physical and biological properties of the blends of bacterial cellulose / alginate sponges have not been clearly elucidated. This study aims to investigate the effects of bacterial cellulose / alginate ratio on the physical and biological properties of developed sponges. The sponges were fabricated by freeze drying of the mixtures with various blending compositions. Results from Fourier transform infrared (FT-IR) spectroscopy proved that bacterial cellulose/alginate sponges in all blending compositions contained only physical but not chemical interaction in molecular level. The mechanical strength of dried sponges decreased with the increasing composition of alginate. Water uptake ratio of the dried sponges was approximately 11-14. The biodegradation test by cellulose enzyme demonstrated that the presence of alginate could prolong the biodegradation of bacterial cellulose/alginate sponges. In vitro culture of keratinocytes and gingival fibroblasts evidenced that pure bacterial cellulose sponges and sponges containing 30% of alginate were effective to promote and accelerate cell proliferation. However, in wet state, only the blend sponge with 30% alginate also had a good tear resistance from sewing. The results indicated that the blends of bacterial cellulose with alginate have high potential to be developed as an alternative material for biomedical approaches.