Rasmus Nielsen (1809, Roerslev, Funen–1884) was a Danish philosopher and professor, as well as a critic of Søren Kierkegaard.Nielsen was the son of a farmer.
He studied theology at the University of Copenhagen, starting in 1832 and graduating in 1837.
He then went on to get a licentiate degree and, after giving some lectures on theological topics, succeeded Poul Martin Møller as professor of moral theology.