Reinhard Keiser
| Reinhard Keiser | |
|---|---|
| Title page of an opera libretto | |
| Born | 9 January 1674 Teuchern, Electorate of Saxony, Holy Roman Empire | 
| Died | 12 September 1739 (aged 65) Hamburg, Holy Roman Empire | 
| Occupations | 
 | 
| Organizations | 
 | 
Reinhard Keiser (9 January 1674 – 12 September 1739) was a German opera composer based in Hamburg. He wrote over a hundred operas. Johann Adolf Scheibe (writing in 1745) considered him an equal to Johann Kuhnau, George Frideric Handel and Georg Philipp Telemann, but his work was largely forgotten for many decades.