| Charles Émile Troisier | |
| Birth Date: | 6 April 1844 |
| Birth Place: | Sévigny-Waleppe, Ardennes, France |
| Death Place: | Paris, France |
| Nationality: | French |
| Occupation: | Surgeon |
Charles Émile Troisier (6 April 1844 – 11 December 1919) was a French surgeon.
Charles Émile Troisier was born on 6 April 1844 in Sévigny-Waleppe, Ardennes. His mother was Marie-Louise Adeline Marache and his father Antoine Édouard Troisier, a health officer at Sévigny.He became a doctor of medicine in Paris in 1874, then a professor at the Faculty of Medicine of the University of Paris and a member of the Académie Nationale de Médecine.
He was made a knight of the Legion of Honour on 6 January 1890.
He had a close relationship with Princess Marie Bonaparte.His son, Jean Troisier (1881–1945), also became a doctor and biologist, and was head of the laboratory at the Pasteur Institute.His granddaughter, Solange Troisier (1919–2008) was a doctor and a leading feminist.
The following are named for him: