The Toki (とき) is a high-speed Shinkansen train service operated by East Japan Railway Company (JR East) on the Joetsu Shinkansen in Japan.

The name is taken from the Japanese name of the crested ibis, for which Niigata is famous.

(*) Not served by all trains

(**) Not served by Toki 311 and 312 only

The name Toki was first introduced on 10 June 1962 for limited express services operating between Ueno in Tokyo and Niigata on the Joetsu Line.These services stopped at Ōmiya, Minakami, Echigo-Yuzawa, Urasa, Nagaoka, Higashi-Sanjō and Niitsu This service operated until 14 November 1982, the day before the Joetsu Shinkansen opened.

From the start of services on the newly opened Jōetsu Shinkansen on 15 November 1982, Toki became the name used for the all-stations shinkansen services operating initially between Ōmiya and Niigata, later between Ueno and Niigata, and eventually between Tokyo and Niigata.

The Toki name was discontinued from October 1997 following the introduction of new Tanigawa all-stations services between Tokyo and Echigo-Yuzawa. However, the name was reinstated from December 2002 to replace the name Asahi used for all Tokyo to Niigata trains.

E2 series 10-car sets were re-introduced on four return Toki services daily from 26 January 2013, operating at a maximum speed of 240 km/h (150 mph).