The goal of supporting and directing tissue regeneration requires the design of new, advanced materials, with features like biocompatibility, biodegradability and adequate mechanical properties. Our work was focused on developing a new injectable biomimetic composite material, based on a peptidic hydrogel and calcium phosphates with the aim of mimicking the chemical composition of natural bone tissue. Arg-Gly-Asp-grafted chitosan was used to promote cell adhesion. The obtained composite hydrogel was characterized with differential scanning calorimetry measurements, rheological analysis, field emission scanning electron microscopy, Fourier transform infrared spectroscopy and nuclear magnetic resonance measurements. The biological responsiveness was assessed using the MG-63 human osteoblast cell line.