Sir Julius Caesar (1557/1558 – 18 April 1636) was an English judge and politician. He was born near Tottenham in Middlesex. His father was Giulio Cesare Adelmare, an Italian physician to Queen Mary and Queen Elizabeth, descended by the female line from the dukes of Cesarini.

He was educated at Magdalen College, Oxford, and afterwards studied at the University of Paris, where in the year 1581 he was made a doctor of civil law. Two years later he was awarded a similar degree at Oxford, and became doctor of the canon law. He represented Reigate, Bletchingley and Windsor in Parliament. He held many high offices during the reigns of Elizabeth and James I, including a judgeship of the admiralty court (1584), a mastership in chancery (1588), treasurer of the Inner Temple in 1593 and a mastership of the court of requests (1595).

He was knighted at Greenwich by King James in May of 1603, and became Chancellor and Under Treasurer of the Exchequer 1606–1614. In 1614 he was appointed Master of the Rolls, an office which he held till his death in 1636. His manuscripts, many of which are now in the British Museum, were sold by auction in 1757 for a sum of around £500. He was also Master of St Katherine's Hospital.

His eldest son (also Julius Caesar) was sent to Padua to study at the university. He was wounded whilst fencing with Antonia Brochetta and sought revenge. He lay in wait for him with a pistol, but his shot missed. He then fell while attempting to draw his sword and was set upon by Brochetta who ran him through and killed him.