Niels Nikolaus Falck (25 November 1784 – 11 May 1850) was a Danish jurist and historian.
He was educated at the University of Kiel and became a theological candidate in 1808, graduating dr. phil.
In 1814, he became professor of law at the University of Kiel, and in 1838 he was appointed president of the Schleswig-Holstein Assembly of the States.
He published a Juristische Encyklopädie (“Encyclopedia of jurisprudence,” 5th ed.
His other works include: Handbuch des schleswig-holsteinischen Privatrechts (“Handbook of civil law in Schleswig-Holstein,” 1825-48); and Sammlungen zur nähern Kunde des Vaterlandes (“Anthology for a better understanding of the fatherland,” 1819-25).