Benjamin Theodor Thierfelder (10 December 1824 – 7 March 1904) was a German internist born in Meissen. He his remembered for contributions made in research of Fieberkurve (temperature patterns) involving typhoid fever.
In 1848 he earned his medical doctorate from the University of Leipzig, where in 1851 he became a member of the medical staff, and an assistant to Carl Reinhold August Wunderlich (1815-1877). In 1855 he was appointed an associate professor at the University of Rostock, where from 1856 to 1901 was a full professor of internal medicine.
He was the brother of pathologist Albert Thierfelder (1842-1908), who was also a professor at the University of Rostock.