James Jackson Putnam (October 3, 1846 – November 4, 1918) was a United States neurologist.
Born in Boston, Massachusetts and graduated from Harvard University in 1866, Putnam went to Europe to study in the company of Baron Carl von Rokitansky, Theodor Meynert and John Hughlings Jackson. On his return to the Massachusetts General Hospital he opened a clinic which became the Department of Neurology at Harvard Medical School.
Putnam was a founder member of the American Neurological Association in December 1874, and was its president in 1888, and also a founding member of the American Psychoanalytical Association in 1911, being its first president and continuing to hold the post the following year. He was appointed Professor of Diseases of the Nervous System at Harvard in 1893 and continued to his retirement in 1912.
In 1900 he was one of the signatories of the “Protest of the Friends of the Present Management of the New York Pathological Institute” together with S. Weir Mitchell, Percival Bailey, Ira Van Gieson, Morton Prince, Frederick Peterson and many others. Putnam was one of those instrumental in bringing Sigmund Freud to the United States in 1909 and became increasingly interested in psychoneurosis and the use of psychotherapy contributing to The Encyclopedia of the Self, writing papers on the necessity of metaphysics and human motives, both later published as books. He also wrote the introduction to the translation from the German of Sigmund Freud's Three Contributions to the Theory of Sex He made a number of contributions to neurology and medicine in general – for example highlighting the fact that hyperthyroidism may terminate in myxoedema. He also did very early investigative work on the basal ganglia.