In this research, the spinnability of bioactive glass (BG) precursor solution was supplied by alkoxysilane sol with appropriate molar ratio of HO/silicon (R) to prepare bioactive glass fiber membrane (BFM) using electrospinning (ES) technique. Alkoxysilane could form a linear or chain-like colloidal aggregation in hydrolysis-polycondensation with R = 2 or so, thereby exhibiting good spinnability. Therefore, the role of polymer binders could be largely replaced. Due to the significant decrease of polymer binder, the defects within the fibers are largely reduced and degree of fiber densification was improved after calcination, leading to BFM drastically enhanced strength and flexibility. The effect of R and calcination temperature on mechanical performance were investigated in detail. The tensile strength could reach the highest value 2.31 MPa with R = 2 and calcination at 700 °C. In addition, under this preparation condition, the BFM also possessed good flexibility with bending rigidity 37.7 mN. Furthermore, the great performance of promoting cell proliferation and osteogenesis could be observed from cellular experiment. The BFM calcined at 750 °C exhibited the best promoting osteogenic differentiation ability. The rat skull defect model revealed BFM could perform well in osteogenesis .