Jan Jesenský Jr. (1904–1942) was a scientist and collaborator of Professor Jan Jesenský at Prague Stomatologic Clinic, assistant professor at Prague University.
Jesenský was born in Prague.
After the occupation of Czechoslovakia by Hitler, he became a member of a secret military resistance organisation.
In 1942 he was arrested by the Gestapo and tortured to death in the Mauthausen concentration camp, Austria.
Jesenský was a cousin of Milena Jesenská.