3 (大阪市高速鉄道第3号線), and in Ministry of Land, Infrastructure and Transport publications, it is written as Line No.

connecting the Osaka Metro Nankō Port Town Line at Suminoekōen Station.

During the morning and evening (afternoon on weekends only), there are trains that only run between Kita-Kagaya station and Nishi Umeda Station, as Kita-Kagaya is connected to the Yotsubashi Line depot at Midorigi.

In addition, on the day of the Suminoe boat race at night (excluding Sundays), one special train operates between 9pm and 10pm.

On 23 March 2013, the Osaka Bureau of Transport revised the timetable for the Yotsubashi Line.