Niwa Nagashige (丹羽 長重, May 11, 1571 – April 30, 1637) was a Japanese daimyō who served the Oda clan.

In 1584, the Battle of Nagakute, at the age of thirteen, Nagashige led a troop of the Niwa clan in place of his father, who was ill.

In 1585, upon Nagahide's death, Nagashige received his father's fief of 1,230,000 koku (spanning Echizen, Wakasa, and parts of Kaga).

However, Toyotomi Hideyoshi was mercurial in his moods, and in response to Nagashige's efforts at the Siege of Odawara, his status was brought back to 120,000 koku.

His daimyo status was restored in 1603, when the Tokugawa family granted him 10,000 koku at Futsuto, in Hitachi Province.