Parathyroid hormone (PTH) and PTH-related peptide (PTHrP) , which were shown to bind the common receptor, PTH/PTHrP receptor, affect fetal chondrogenesis and adult bone turnover, respectively. PTH appears to predominantly stimulate proliferation of osteoblastic precursors, and consequently affect osteoblastic differentiation mediating coupling with osteoclasts. A recent study has reported the biological function of C-terminal region of PTHrP including nucleolar targeting signal. We will review recent reports for the action of PTH and PTHrP on bone and cartilage.