Andreas Aagesen (August 5, 1826 - October 26, 1879) was a Danish jurist.
Aagesen studied law at Kristianshavn and Copenhagen, interrupting his studies in 1848 to take part in the First War of Schleswig, serving as the leader of a reserve battalion. In 1855 he became professor of jurisprudence at the University of Copenhagen (Københavns Universitet). In 1870 he was appointed a member of the commission for drawing up a maritime and commercial code, and the navigation law of 1882 is mainly his work. In 1879 he was elected a member of the Upper House of the Danish Parliament. His reputation is mainly based on his work as a professor in the university. Among his numerous juridical works may be mentioned: Bidrag til Læren om Overdragelse af Ejendomsret, Bemærkinger om Rettigheder over Ting (Copenhagen, 1866, 1871-1872); Fortegnelse over Retssamlinger, Retslitteratur i Danmark, Norge, Sverige (Copenhagen, 1876). Aagesen was Carl Christian Hall's successor as lecturer on Roman law at the university, and in this department his researches were epoch-making.