Gelatin-hydroxyapatite (HG) nanocomposites have an inorganic nanostructure similar to that of bone. However, HG nanocomposites exhibit only osteoconductivity and not osteoinductivity. Recently, stem cell seeding on nanocomposite scaffolds has been attempted, in an effort to improve osteoinductivity. The present study examined the effects of gelatin and glutaraldehyde (GA) addition on the structural features of an HG nanocomposite scaffold containing stem cells. HG nanocomposites were fabricated by the precipitation of hydroxyapatite within a gelatin matrix. Four materials were synthesized as follows: HG3 (10 g HA in 3 g gelatin solution), HG3+GA (10 g HA in 3 g gelatin solution; GA addition), HG4 (10 g HA in 4 g gelatin solution), HG4+GA (10 g HA in 4 g gelatin solution; also termed GA addition). After fabrication, scaffolds were seeded with adipose tissue-derived stromal cells (ADSCs) obtained from rabbit suprascapular fat pads. After cell culture, osteogenic inductivity was tested by appropriate staining, scanning electron microscopy (SEM), colorimetric assays, biochemical tests for alkaline phosphatase (ALP), and an osteocalcin (OC) detection kit. Cell attachment to the scaffold surface was observed by SEM. Cell viability in scaffolds was quantified using the MTS assay. The maximum ALP and OC contents were seen in HG3-derived material. Substrates with added GA showed lower ALP and OC levels than did those without GA. The HG3 group without GA showed the best response with respect to attachment, proliferation, and osteogenic differentiation of ADSCs. These findings suggest that a HG nanocomposite scaffold with ADSCs may be osteoinductive.