Friedrich Jolly (November 24, 1844 – January 4, 1904) was a German neurologist and psychiatrist who was a native of Heidelberg, and the son of physicist Philipp von Jolly (1809–1884).
He studied medicine at Göttingen under Georg Meissner (1829–1905), and in 1867 received his doctorate at Munich. In 1868 he became an assistant to Bernhard von Gudden (1824–1886) and Hubert von Grashey (1839–1914) at the mental institution in Werneck, and in 1870 was an assistant to Franz von Rinecker (1811–1883) at the Juliusspital in Würzburg.
In 1873 Jolly became director of the psychiatric clinic in Strassburg, where he was named as successor to Richard von Krafft-Ebing (1840–1902). In 1890 he succeeded Karl Friedrich Otto Westphal (1833–1890) as director of the neuropsychiatric clinic at the Berlin Charité.
Jolly is remembered for his pioneer research of myasthenia gravis, including the electrophysiological aspects involving abnormal fatigue associated with the disease which forms the basis of Jolly's test. He is credited with coining the term myasthenia gravis pseudoparalytica for the disorder.