The Ma On Shan Line (formerly called Ma On Shan Rail, Chinese: 馬鞍山鐵路, abbreviated as 馬鐵) is a branch line of the East Rail Line in Hong Kong. Originally, the railway was operated by Kowloon-Canton Railway Corporation (KCRC). It is now operated by MTR Corporation as one of the ten lines of the MTR, after the merger of operations on 2 December 2007.