The section between Den-en-chofu and Hiyoshi Station is a quadruple track corridor with the Tōkyū Meguro Line.

Upbound-wise some Express Trains will through operate into Tokyo Metro Fukutoshin Line as local services.

Downbound-wise, some Express Trains will through operate into Tōkyū Shin-Yokohama Line after Hiyoshi instead of continue onward to Yokohama/Motomachi-Chūkagai.

Through an engineering project culminating in a dramatic single overnight maneuver, the existing surface rail line was disconnected, sunken, and reconnected with the new underground line in time for the normal morning train schedule to run.

As a result of the new connection, the original elevated Shibuya terminal for Tokyu trains was abandoned and demolished.

The line was extended incrementally until the entire length from Shibuya to Sakuragichō in Yokohama was opened on 31 March 1932.

On 29 August 1964, through service to the Tokyo Metro Hibiya Line via Naka-Meguro Station was started.

[18] On 16 March 2013, the 1.4 km (0.87 mi) section between Shibuya to Daikan-yama was replaced with an underground connection to the Tokyo Metro Fukutoshin Line.

[19] Just four hours later, at 5 am, trains began calling at a new set of underground platforms adjacent to those previously served only by the Fukutoshin Line.

[20] During this time, 1,200 workers shifted the track alignment at Daikan-yama Station along a pre-built incline.

[21] Since that day, Tokyu and Yokohama Minatomirai Railway trains commenced through running onto the Fukutoshin Line and beyond.

Tokyo Metro, Tobu, and Seibu also started operating their trains through to the Tōyoko and Minatomirai Lines.

[27] On 15 February 2014, two trains collided and derailed at Motosumiyoshi station resulting in nineteen injuries.