Andreas Clemmensen (7 August 1852 – 5 December 1928) was a Danish architect and royal building inspector.

[1] Clemmensen was born on 7 August 1852 in Leck, Duchy of Schleswig, the son of Carl Frederik Clemmensen and Charlotte Laurence Hass.

He trained at C.V. Nielsens Tegneskole and was admitted to the Royal Danish Academy of Fine Arts in 1867, from which he left as an architect in 1875.

During his studies he was a draftsman for Johan Daniel Herholdt and Hans J. Holm.

He died on 5 December 1928 in Copenhagen and is buried at Assistens Cemetery.