Nikoloz "Niko" Dadiani (Georgian: ??????? "????" ???????), or Nikolay Davidovich Dadian-Mingrelsky (Russian: ??????? ????????? ??????-????????????; 4 January 1847 – 23 January 1903), was the last Prince of Mingrelia from 1853 to 1867.
Of the House of Dadiani, one of the leading Georgian noble families, he succeeded on the death of his father, David Dadiani, but he never ruled in his own right; during his minority, the government was run by regency presided by his mother, Princess Ekaterina, and in 1857, Mingrelia was placed under a provisional Russian administration.
In 1867, Dadiani formally abdicated the throne and Mingrelia was directly incorporated into the Russian Empire.
Dadiani mostly lived in Saint Petersburg, being close to the court.
He was an officer in the Imperial Russian Army, distinguished himself in the Russo-Turkish War (1877–1878), and retired with the rank of major-general.