Lluís Nicolau d'Olwer (20 January 1888 in Barcelona – 24 December 1961 in Mexico City) was a Catalan politician, historian and writer.

He served as the Minister of Economics in the provisional government of the Second Spanish Republic from April to December 1931 and later headed the Bank of Spain (1936–38).

A son of the notary Joaquín Nicolau and Anna d'Olwer (who was of Irish ancestry), he studied philosophy and literature in Barcelona before completing a doctorate in Madrid.

In 1918, he became a member of the philology department of the Institute of Catalan Studies and a representative of the Regionalist League in the municipality of Barcelona.

[1] As a member of the Cultural Committee, he initiated modern teaching policies and in 1922 was a co-founder of the Acció Catalana.