The Nisshin Maru (日新丸) was the primary vessel[5] of the Japanese whaling fleet and was the world's only whaler factory ship.

The ship was based in Japan in Shimonoseki harbor[8] and was owned by Tokyo-based Kyodo Senpaku, which is a subsidiary of the Institute of Cetacean Research.

[37] Sea Shepherd Conservation Society claimed its president Paul Watson was shot by someone aboard Nisshin Maru during a confrontation with the MY Steve Irwin off Antarctica in 2008.

[39] In March 2011, Nisshin Maru returned early from operations in the Southern Ocean and immediately began assisting in disaster relief efforts following the 2011 Tōhoku earthquake and tsunami, transporting food, fuel, and other supplies to areas devastated by the catastrophe.

[40] In February 2013, Nisshin Maru was involved in a multiple-ship collision, colliding with the Sea Shepherd vessels Steve Irwin, MY Bob Barker, and MY Sam Simon,[41] as well as the whaler's refueling ship, Sun Laurel.

Additional regulations from the United Nations International Maritime Organization (IMO) took effect on August 1, 2011 prohibiting ships using heavy oil fuel below 60 degrees south to prevent pollution.