The Osaka Municipal Subway/Osaka Metro 66 series (大阪市交通局・大阪メトロ66系) is a rapid transit electric multiple unit (EMU) train type operated by Osaka Municipal Subway in Japan since 1990.

[1] Seventeen eight-car sets were built to replace the older 60 series sets on the Sakaisuji Line.

[1] The Sakaisuji Line fleet consists of 17 eight-car trainsets formed as follows, with car 1 at the Tenchagaya end.

Passenger accommodation consists of longitudinal seating throughout.

[2] Works included a new paint scheme, various installations of LED displays and lights, and the installation of a front skirt.