Abstract: Plant plasma membrane H+ -ATPase was a P-type proton pump. The transmembrane electrochemical gradients generated by the enzyme was the primary force for the transmembrane transports. Researches indicated that the plasma membrane H+ -ATPase plays important roles in the growth and development in plants. It was called the "master enzyme" in plant cells; Great progress had been made about the biochemical character, gene expression and regulation, structure and function of the H+ -ATPase in recent years. In this article the biochemical character, molecular structure, regulatory mechanism and physiological roles of the plasma membrane H+ -ATPase were reviewed.