Fracture healing is a process comprising of a local bleeding followed by inflammation and differentiation of mesenchymal cells that lead to formation of soft extracellular matrix tissue, cartilage and bone. This pathway includes endo-chondral bone formation and in part intra-membranous bone formation. During this process several sets of cytokines are involved in the regulation of the progress in fracture healing. This paper reviews the molecules involved in fracture healing.