The Tokyo Metro Yurakucho Line (東京メトロ有楽町線, Tōkyō Metoro Yūrakuchō-sen) is a subway line in Japan owned and operated by Tokyo Metro. The line connects Wakōshi Station in Wakō, Saitama and Shin-Kiba Station in Kōtō, Tokyo. On maps, diagrams and signboards, the line is shown using the color "gold", and its stations are given numbers using the letter "Y".
The line was named after the Yūrakuchō business district in Chiyoda, Tokyo. The proper name as given in an annual report of the Ministry of Land, Infrastructure and Transport is Line No. 8 Yūrakuchō Line (8号線有楽町線, Hachi-gō-sen Yūrakuchō-sen). According to the Tokyo urban transportation plan, however, it is more complicated. The line number assigned to the section south from Kotake-Mukaihara to Shin-Kiba is Line 8, but that north of Kotake-Mukaihara to Wakōshi is Line 13, which indicates the section is a portion of Fukutoshin Line which shares the same number.