Here, the fabrication and characterization of porous magnetic nanocomposites was carried out via the blending of chitosan, polyethylene glycol and nano-hydroxyapatite-Fe3O4. Scanning electron microscope images revealed a highly interconnected macro- and micro-porous structure. These nanocomposites showed good water uptake abilities and have good antimicrobial properties. The tensile strengths of these nanocomposites were enhanced significantly compared to previously reported results, after the addition of nano-Fe3O4. Moreover, these nanocomposites could be applied for magnetic therapy as this material exhibited superparamagnetic properties. Finally, these nanocomposites were good supports for human osteoblast-like MG-63 cells' growth, attachment and proliferation and they showed good cytocompatibility. No negative effect on the MG-63 cells was observed, suggesting that these nanocomposites have great potential to be applied for bone regeneration. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.