Ephraim Chambers (c1680 - 15 May 1740), was an English encyclopaedist.

He was born in Kendal, Westmorland, in the latter part of the 17th century. He was apprenticed to a globe-maker in London, but having conceived the plan of his Cyclopaedia, or Universal Dictionary of Arts and Sciences, he devoted himself entirely to it. The first edition. appeared by subscription in 1728, in two vols. fol., and dedicated to The King . The Encyclopedie of Diderot and d'Alembert owed its inception to a French translation of Chambers's work. In addition to the Cyclopaedia, Chambers wrote for the Literary Magazine (1735-1736), and translated the History and Memoirs of the Royal Academy of Sciences at Paris (1742), and the Practice of Perspective from the French of Jean Dubreuil .