Charles Joseph Singer (2 November 1876 – 10 June 1960) was a British historian of science, technology, and medicine.

Forced to return to England on his father's death in 1908, he held positions at various hospitals in London until he moved to Oxford in 1914 to work with Sir William Osler, then Regius Professor of Medicine at the university.

Singer was married in July 1910 to Dorothea Waley Cohen, distinguished in her own right as an historian of the Medieval period.

Singer accepted a commission as medical officer in the British Army in 1916, first as a pathologist and then as part of an archaeological expedition.

Johns Hopkins was also interested in offering him a permanent post, but their delay allowed the University of London to award him an honorary chair, which he accepted.

He was invited again by the University of California at Berkeley to lecture in 1932, an occasion that the Singers used to circle the globe going westward, spending about sixteen months away from England.

Singer was one of the two contributors to the revised and updated version for Encyclopædia Britannica of the bulk of Thomas Clifford Allbutt's article Medicine which had been in the 11th edition.