Nikolaus Joseph Freiherr von Jacquin[1] (16 February 1727 – 26 October 1817) was a scientist who studied medicine, chemistry and botany.

In 1797, Alexander von Humboldt profited from studying these collections and conversing with Jacquin in preparation of his own journey to the Americas.

In 1768, he was appointed Professor of Botany and Chemistry and became director of the botanical gardens of the University of Vienna.

Mozart dedicated a considerable number of his works to the Jacquin family, notably the Kegelstatt Trio.

His son Joseph Franz (1766–1839) succeeded him as professor of botany and chemistry at the University of Vienna and wrote several notable botanical books.