Bones are rigid, dynamic biological organs where a series of active cells reside and fit within a rigid matrix and this structure physically supports and protects the tissues and organs of our body. Bones store minerals, and the bone marrow in the bone structure produces new blood cells. More than 270 pieces of bone are found in the bodies of infants, and many of them fuse together during growth. These bones come in different shapes and have complex and hierarchical structures. With different shapes, mechanical properties and biological activities, they play various roles in our body functions. In this review article, we mainly focus on long bone healing, regeneration and tissue engineering strategies. A series of mechanisms such as biochemical mechanisms, bone cell biology, hormonal and pathological mechanisms have an attributable effect on the progression of bone tissue healing. Osteoblasts, osteoclasts, and osteocytes are three major cells related to bone tissue regeneration that contribute to the completion of injury healing. Differentiated from mesenchymal stem cells (MSC), the main function of osteoblasts is to build bone extracellular matrix (ECM), called osteoid, by producing and secreting organic compounds, such as type I collagen. Osteoblasts are also involved in mineralization, where osteoblasts secrete alkaline phosphatases which modify phosphate groups to become sites of mineral deposition [1]. When forming bone, osteoblasts have two pathways to follow. One of these two phenomena consists of remaining trapped in the matrix secreted by the osteoblasts themselves and differentiating into osteocytes, and the other of undergoing programmed cell death, called apoptosis [2]. Osteoblasts affect skeletal architecture in two major aspects: bone matrix deposition...... middle of article ......): p. 412-20.10. DePalma, AF, et al., Anterior interbody fusion for severe cervical disc degeneration. Surg Gynecol Obstet, 1972. 134(5): p. 755-8.11. Kalfas, IH, Principles of bone healing. Neurosurgical Focus, 2001. 10(4): p. 1-4.12. LaStayo, PC, KM Winters, and M. Hardy, Fracture Healing: Bone Healing, Fracture Management, and Current Hand-Related Concepts. J Hand Ther, 2003. 16(2): p. 81-93.13. Marsell, R. and TA Einhorn, The biology of fracture healing. Injuries, 2011. 42(6): p. 551-555.14. Dimitriou, R., E. Tsiridis and PV Giannoudis, Current concepts of molecular aspects of bone healing. Injury-International Journal of Injury Care, 2005. 36(12): p. 1392-1404.15. Gerstenfeld, LC, et al., Three-dimensional reconstruction of fracture callus morphogenesis. Journal of Histochemistry and Cytochemistry, 2006. 54(11): p. 1215-1228.