The year 1858 in architecture involved some significant events.

• The competition to design Central Park in New York City is won by Frederick Law Olmsted and Calvert Vaux.
• Eugène Viollet-le-Duc begins publication of his Entretiens sur l'architecture in book form, systematizing his approach to architecture and architectural education in a method radically opposed to that of the École des Beaux-Arts, and notable for its use of drawings in axonometric projection.

• The Hamilton Mausoleum in Scotland is completed to an 1842 design by David Hamilton by David Bryce with sculptor Alexander Handyside Ritchie.
• Saint Isaac's Cathedral in Saint Petersburg (Russia) is completed to an 1818 design by Auguste de Montferrand.
• Trinity Church (Oslo) in Norway, designed by Alexis de Chateauneuf and Wilhelm von Hanno, is consecrated.
• New parish Church of St George, Doncaster, Yorkshire, England, designed by George Gilbert Scott, is consecrated.
• Wesley Church, Melbourne, Australia, is opened.
• Leopoldstädter Tempel (synagogue) in Vienna, designed by Ludwig Förster, is built.
• Grand Synagogue of Aden is built.
• Church of the Resurrection in Katowice (Poland) is completed.
• Fishergate Baptist Church in Preston, Lancashire (England), designed by James Hibbert and Nathan Rainford, is completed.
• Leeds Town Hall in Yorkshire (England), designed by Cuthbert Brodrick, is completed.
• Ontario County Courthouse in Canandaigua, New York, is built.
• United States Customhouse and Post Office (Bath, Maine) is built.
• The Liverpool, London and Globe Building (insurance office) in Liverpool (England), designed by C. R. Cockerell, is completed.
• The West of England and South Wales Bank in Bristol (England), designed by Bruce Gingell and T. R. Lysaght, is completed.
• The rebuilt Royal Opera House, Covent Garden, London, designed by Edward Middleton Barry, is completed.
• St James's Hall (concert hall), Piccadilly, London, designed by Owen Jones, is opened.
• Hownes Gill Viaduct in County Durham, England, designed by Thomas Bouch, is opened.
• New westwork at Speyer Cathedral (Bavaria), designed by Heinrich Hübsch, is completed.
• Construction of Woodchester Mansion (Spring Park) in Gloucestershire, England, designed by Benjamin Bucknall, is begun; work is abandoned in the 1870s.

• RIBA Royal Gold Medal – Friedrich August Stüler.
• Grand Prix de Rome, architecture: Georges-Ernest Coquart.

• March 9 – Gustav Stickley, American furniture designer and architect (died 1942)
• August 9 – John William Simpson, English architect (died 1933)
• October 30 – Wilson Eyre, American architect (died 1944)
• December 26 – Torolf Prytz, Norwegian architect, goldsmith and Liberal politician (died 1938)
• Leonard Stokes, English architect (died 1925)

• February 19 – Alexander Black, Scottish architect (born c.1790)
• February 24 – Thomas Hamilton, Scottish architect (born 1784)
• June 28 – Auguste de Montferrand, French-born architect (born 1786)
• November 12 – Edward Cresy, English architect and civil engineer (born 1792)
• November 14 – Benjamin Green, English architect (born 1813)