 Unlike other Tokyu lines that are heavy rail commuter lines, the Setagaya Line is governed under the of the Japanese government.Despite this, the entire line is located on its own right-of-way because it is a branch line of , which is not the same line as the present-day Tōkyū Tamagawa Line.The Setagaya Line was opened by the in 1923, running on surface streets between Shibuya and the Tama River.