August Sicard von Sicardsburg

August Sicard von Sicardsburg (6 December 1813 – 11 June 1868) was an Austrian architect. He is best remembered as the co-architect of the Vienna State Opera, together with Eduard van der Nüll.

Sicardsburg was born in Buda. He studied architecture at the Vienna University of Technology under Peter von Nobile, and together with van der Nüll. In 1843 he became professor at the Vienna Academy.

Karl Freiherr von Hasenauer was one of his students.

Sicardsburg died in 1868 in Weidling, Austria of tuberculosis, 6 weeks after his partner Eduard van der Nüll committed suicide; neither saw the opening of the Vienna State Opera in 1869.