The Muar State Railway (MSR) (Malay: Keretapi Kerajaan Muar ; Jawi: كريتاڤي كراجأن موار) was a railroad operating in the district of Muar in Johor, Malaya (now Malaysia). Significantly, the MSR was the second railway line to operate in Johor after the short-lived Johore Wooden Railway (JWR), and began operation in 1890, five years after the opening of Perak Railway's Taiping-Port Weld line.