Okazaki Station was opened June 16, 1891 when the section of the Japanese Government Railways (JGR) line connecting Hamamatsu with Obu was completed. This line was named Tōkaidō Line in 1895, and the Tōkaidō Main Line in 1909. The Nishio Railway began operations to Okazaki Station from October 30, 1911 (later taken over by Meitetsu, operations were discontinued in 1943). In 1930, the first bus system operated by the national government began operations from Okazaki Station. After World War II, the JGR became the Japan National Railway (JNR). A portion of the former Nishio Line was reopened on December 1951 as the "Fukuoka Line", which operated to June 1962. The JNR Okata Line (the forerunner of the Aichi Loop Line) began freight operations in October 1970 and passenger operations in April 1976. However, all freight operations from Okazaki Station were discontinued in January 1984 and small parcel operations from November 1986. With the privatization and dissolution of the JNR on April 1, 1987, the station came under the control of the Central Japan Railway Company. A new elevated station building was completed in October 1990.