AbstractThis study focuses on developing a sustainable and biocompatible polycaprolactone (PCL)‐based scaffold for bone tissue engineering through electrospinning, utilizing calcium carbonate (CaCO3) from Pomacea canaliculata shells and keratin from human hair, known for stimulating bone regeneration. The isolated CaCO3 has been identified to demonstrate two polymorphs, vaterite and calcite, as determined by X‐ray diffraction. The isolation of keratin from human hair was confirmed through sodium dodecyl sulfate polyacrylamide gel electrophoresis and Fourier transform infrared spectroscopy analysis, revealing the presence of α‐keratin structures around 45–50 kDa and β‐keratin structures around 55–60 kDa. According to scanning electron microscope observations, the addition of keratin to PCL fibers reduced their diameter from 457 ± 345 to 371 ± 103 nm. Further addition of calcium carbonate led to a mean diameter of 258 ± 76 nm. The melting temperature of PCL fibers containing keratin and CaCO3 was determined to be 76.17 °C via differential scanning calorimetry, while thermogravimetric analysis, conducted at temperatures up to 600 °C, revealed a remaining ash content of 9.59%. Calcium phosphate accumulation was observed to initiate on PCL fibers containing keratin and CaCO3 following a 7‐day exposure to simulated body fluid. The fibers exhibit cytocompatibility, showing no toxicity while supporting the growth and proliferation of Saos‐2 osteosarcoma cells. The results suggest that the innovative incorporation of keratin and CaCO3 into PCL nanofibers could serve as a bioactive matrix compared to pure PCL matrices, thereby offering enhanced potential for bone tissue engineering applications. © 2024 The Author(s). Polymer International published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.