Mineralization of electrospun chitosan/poly(vinyl alcohol) (PVA) with CaCO3 was performed as a reinforcement strategy to produce a biocompatible material with good mechanical properties. Disk-like layered and cubic CaCO3 particles were formed when the composites were dried at low and high concentrations of CO2, respectively, followed by a transformation of the amorphous CaCO3 into calcite. The highest ultimate stress value was found to be 44 +/- 3.2 MPa for the composite with 17 wt% of CaCO3, which was crosslinked by glutaraldehyde and dried at high concentrations of CO2. The highest value of the Young's modulus was 2328.35 +/- 204.9 MPa for the composite with 34 wt% of CaCO3 that was dried at high concentrations of CO2. The bioactivity of the obtained composites was tested by 6-day incubation in simulated body fluid (SBF), resulting in flake-like apatite structures grown on the composite surface. The composites retained around 50 % of their ultimate stress value after immersion in SBF. The mineralization of electrospun chitosan/PVA with CaCO3 produced composites with enhanced mechanical properties, which can be potentially used as scaffolds in tissue engineering applications.