Bone marrow mesenchymal stem cells (BMSCs) possess a high replicative capacity and have the capacity to differentiate into various connective tissue cell types. With the advance in cell culture technique, the BMSCs have been induced to differentiate to osteoblastics linage. To improve the situation of non-union in posterior spinal fusion (PSF), tissue engineering approach to combine BMSCs supported by the calcium phosphate ceramics was applied in PSF and its effect was investigated in the present study. Autologous BMSCs from 16-week-old rabbit tibiae were expanded and induced to differentiate into osteoblastic cells with defined medium and osteogenic supplement. Calcium phosphate ceramic (CPC) was used as the scaffold to deliver the cells to the standardized rabbit posterior spinal fusion model. The assessment of bone mineral and fusion mass volume was conducted at week 7 post-operation with quantitative computed tomography and micro-computed tomography. When compared with control, the composite of BMSCs with CPC enhanced the fusion mass volume by 40% (p<0.05) and bone mineral content in the CPC was 7% (p=0.05) higher. Our study showed that additional BMSCs at the fusion site of PSF did provide extra resource for new bone formation and enhanced the fusion rate.