Louis Heilprin (July 2, 1851[1]–1912) was a Hungarian American author, historian, and encyclopedia editor.
His father, Michael, son of Phineas Mendel, was also an encyclopedist and scholar of Hebrew history and literature and a follower of Lajos Kossuth.
He had a younger brother Angelo who was a professor at the Philadelphia Academy of Sciences and two sisters.
The family left Hungary as refugees in 1856.
He also wrote articles for The Evening Post and The Nation.