The E4 series (E4系?) is a high-speed shinkansen train type operated by East Japan Railway Company (JR East) in Japan. They were the second series of completely bi-level Shinkansen trainsets to be built in Japan (the other being the E1 series). They operate on the Tōhoku and Jōetsu Shinkansen, and occasionally on the Nagano Shinkansen. E4 series trains feature double-decker cars to accommodate additional commuter traffic around Tokyo and other urban areas. They were often coupled to 400 series trains on the Tōhoku Shinkansen between Tokyo and Fukushima before the latter retired in April 2010.
Two eight-car sets can be coupled together for extra capacity: a sixteen-car E4 series formation trainset carries a total of 1,634 seated passengers - the highest-capacity high-speed rail trainset in the world.
26 units were built between 1997 and 2003. As with the earlier E1 series trains, maximum speed is 240 km/h (150 mph).