The shōgun Tokugawa Ieyasu bequeathed land in this area to a Naitō daimyō (feudal lord) in 1590 for his residence in Edo.

[1] Most of the garden was burnt and greatly damaged by air raids in 1945, in the later stages of World War II, except for the Taiwan Pavilion.

[1] The 1989 state funeral rites of emperor Hirohito were held in the garden, before he was taken for burial at the Musashi Imperial Graveyard.

The garden is a favourite hanami (cherry-blossom viewing) spot, and large crowds can be present during cherry blossom season.

The present greenhouse, built in the 1950s, has over 1,700 tropical and subtropical plant species on permanent display.

Shinjuku Gyoen is open from 9:00 until 17:30 (mid-March until end of September; October–mid-March: until 16:00; July–late August: 18:30).