The year 1891 in science and technology included many events, some of which are listed here.

Awards

• Copley Medal: Stanislao Cannizzaro
• Wollaston Medal for Geology: John Wesley Judd

Births

Deaths

• February 10 - Sofia Kovalevskaya (b. 1850), mathematician.
• May 11 - Alexandre-Edmond Becquerel (b. 1820), physicist.
• June 23 - Wilhelm Eduard Weber (b. 1804), physicist.
• November 18 - Joseph Wolstenholme (b. 1829), mathematician.