The Keisei Main Line (京成本線, Keisei Honsen) is a railway line of Japanese private railway company Keisei Electric Railway connecting Tokyo and Narita, Japan.

Built as an interurban between Tokyo and Narita in the early 20th century, the line has served as a main access route to Narita International Airport since 1978.

It also serves major cities along the line such as Funabashi, Narashino, and Sakura.

JB Chūō-Sōbu Line (Motoyawata: JB28) All sections opened as electrified dual track unless noted otherwise.

The initial section opened between Takasago and Edogawa as 1,372 mm (4 ft 6 in) gauge in 1912, and the line was progressively extended in both directions, reaching Narita in 1930 and Ueno in 1933.