The study of inorganic hydroxyapatite (HA) assembly in polymer matrix is of great interest in bone tissue engineering field. An in situ synthesis method is employed in this study to synthesise carboxymethyl cellulose (CMC)/HA composite scaffolds to mimic the natural bone. The formation of HA in CMC matrix is initiated at three different temperature (30 °C, 60 °C and 90 °C) and the size of HA decreased with the increase of temperature. The morphology of the scaffolds as viewed by scanning electron microscope shows the formation of rough surfaces with agglomerated HA that can favour appreciable attachment of cells. The X-ray diffraction and Fourier transform infrared spectroscopy confirmed the purity of the formed HA in the polymer matrix. The mechanical properties of the scaffolds reveal that they can form suitable templates to support newly formed bone cells at the site of the defect. The cytotoxicity test of scaffolds with the fibroblast (NIH3T3) cells demonstrated that they can form a suitable template for the attachment of cells and proliferation in bone regeneration. [Figure not available: see fulltext.]. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.