Purpose: The purpose of this in vitro study was to examine the effect of dissociated soft tissue on bone marrow cell proliferation and differentiation under osteogenic conditions. Materials and Methods: Rat bone marrow cells were cultured to assess the stimulation of cell proliferation and differentiation. Harvested palatal mucosa was dissociated using a device (Rigenera, Human Brain Wave), and the dissociated soft tissue was cultured with rat bone marrow cells. Cell proliferation, differentiation, and mineralized nodule formation were assessed after 2 or 5 days of culturing. Bone marrow cell proliferation was assessed by quantifying the absorbance of a water-soluble tetrazolium salt using a cell proliferation assay kit. Bone marrow cell differentiation was assessed by alkaline phosphatase staining and real-time polymerase chain reaction. Mineralized nodule formation was assessed by Alizarin red staining. Results: At day 2, cell proliferation, osteoblast-specific gene expression, and mineralized nodule formation were significantly higher in the experimental group than in the control group. Alkaline phosphatase staining was also higher in the experimental group on day 2. Mineralized nodule formation area and osteoblast-specific gene expression were also statistically higher in the experimental group on day 5. Conclusion: This study demonstrates that dissociated soft tissue elevates bone marrow cell proliferation and differentiation under osteogenic conditions. Keywords: bone regeneration, dissociated soft tissue solution, in vitro study, palatal mucosa