|Died||8 December 1877
|Awards||RIBA Royal Gold Medal|
|Buildings||The circular reading room at the British Museum|
Sydney Smirke RA (1798 – 8 December 1877) was a British architect who was born in London, England, the younger brother of Sir Robert Smirke, also an architect. Their father, also Robert Smirke, had been a well-known 18th-century painter.
Sydney Smirke's works include:
- Customs House (refronting), Quayside, Newcastle upon Tyne, (1833)
- The Custom House, Queen Square, Bristol (1835–57)
- Wellington Pit Surface Buildings (Whitehaven) (1840)
- The nave roof of York Minster (1841)
- Holy Trinity Church, Bickerstaffe, Lancashire (1843)
- The Carlton Club in Pall Mall, London (1845)
- The Custom House, Commercial Road, Gloucester (1845)
- The dome chapel of the Bethlem Royal Hospital, St George's Fields, Southwark (now housing the Imperial War Museum) (1846)
- The Frewen Mausoleum at St Mary's Church, Northiam, East Sussex (1846)
- St. James' Church, Westhead, Lancashire (1850)
- St Mary the Virgin's Church, Theydon Bois (1850)
- The Derby Hall, Derby Hotel and Athenaeum in Bury (1849–52; the latter two now demolished)
- The circular reading room at the British Museum (1857)
- King Edward's School, Witley, Surrey (1865)
- Exhibition galleries at Burlington House, home o the Royal Academy (1868)
- Hall of Inner Temple (1870)
- St John's Church, Loughton
- Landscaping of Brookwood Cemetery, near Woking, Surrey (with William Tite)
- Toll House, Lower Sandgate Road, Folkestone 
He received the RIBA Royal Gold Medal in 1860. He became an associate of the Royal Academy in 1847 and was elected a full Academician in 1859. He served as RA Treasurer from 1861 to 1874, and was professor of Architecture from 1860 to 1865.
Among Smirke's numerous apprentices was the successful York architect George Fowler Jones.
- Historic England. "Parish Church of St Mary (1337290)". National Heritage List for England. Retrieved February 2016. Check date values in:
- "Toll House – Lower Sandgate Road – Folkestone, Kent UK". www.waymarking.com. 4 January 2012. Retrieved 22 December 2013.
- Fawcett, Jane (Editor), Seven Victorian Architects, Thames and Hudson, 1976. ISBN 0-500-34070-6
- Gentleman's Magazine, 1841, Part 1, p91
- Oxford Dictionary of National Biography