| Jakob Meisenheimer | |
| Birth Date: | 14 June 1876 |
| Birth Place: | Griesheim (Frankfurt am Main), German Empire |
| Nationality: | German |
| Death Place: | Tübingen, Germany |
| Work Institution: | University of Munich, University of Greifswald, University of Tübingen |
| Alma Mater: | University of Munich |
| Doctoral Advisor: | Friedrich Karl Johannes Thiele |
| Known For: | Meisenheimer complex, Mechanism of the Beckmann rearrangement |
Jakob Meisenheimer (14 June 1876 - 2 December 1934) was a German chemist. He made numerous contributions to organic chemistry, the most famous being his proposed structure for a group of compounds now named Meisenheimer complex.[1] He also proposed the mechanism of the Beckmann rearrangement. Later in his career, he reported the synthesis of the pyridine-N-oxide.