Yotsuya-sanchōme Station consists of two side platforms.

Platform one is for trains bound for Shinjuku, Ogikubo and Nakano-fujimichō, and platform two is for trains bound for Ginza and Ikebukuro.

The station facilities were inherited by Tokyo Metro after the privatization of the Teito Rapid Transit Authority (TRTA) in 2004.

[1] The station is underneath the intersection of National Route 20 (Kōshū Kaidō / Shinjuku-dōri) and Tokyo Metropolitan Route 319 (Gaien-Higashi-dōri).

Other points of interest include: Stop: Yotsuya-Sanchome Hōnanchō Branch Line