Oscar Faber (1886-1956) was a structural engineer born in 1886 to the son of the Danish Commissioner of Agriculture in London.

Faber was influential in the development of the use of reinforced concrete in the United Kingdom. Because many engineers were not certain of the material, Faber pioneered simple deflection tests, which enabled him to develop his theory of 'plastic yield in concrete’, and to calculate shear in reinforced concrete beams.

Notable projects include the Bank of England, the House of Commons, Africa House, India House in London and Snowhill, Bath, a re-development scheme consisting of 11 storey blocks of 56 maisonettes. He co-authored the book, Reinforced Concrete Design with P G Bowie, which became a standard work. Faber's work on the House of Commons won him a CBE in 1951.

Faber was president of the Institution of Structural Engineers between 1935 and 1936. The Institution named an award after him, the Oscar Faber Medal, one of which was presented to Fazlur Khan in 1973.

Faber's company Oscar Faber and Partners eventually merged with Maunsell to become Faber Maunsell, and was was rebranded AECOM in 2009.