Osteoblast plays an important role in the regulation of bone metabolism.The bone formation and loss are affected by osteoblast differentiation and apoptosis.There are many regulating factors effect on the processes of osteoblast formation,differentiation and apoptosis.This paper summarized the osteoblast functions in bone metabolism,these factors regulation on the osteoblast formation,differentiation and apoptosis,and osteoblast differentiation signal pathway.