After graduation from Lafayette College in Easton (1880), he went to Germany and studied with philosopher Rudolf Hermann Lotze at the University of Göttingen and with psychologist Wilhelm Wundt at the University of Leipzig. Returning to the U.S., he spent 1882 and 1883 at Johns Hopkins University, Baltimore. Journeying again to Leipzig, he became Wundt's assistant and conducted investigations directed toward scientific objectivity.

After receiving his Ph.D. from Leipzig (1886), Cattell continued his research in the London laboratory of Sir Francis Galton. In 1888 he received a professorship in psychology, the first ever offered, at the University of Pennsylvania, Philadelphia. There he established a laboratory and developed a series of mental measurement tests for college students.

In 1891 Cattell became professor and administrative head of psychology at Columbia University and devoted much of his career there to the improvement and advancement of mental testing. In 1894 he cofounded the Psychological Review and acquired the weekly journal Science, which he edited from 1894 to 1944. In 1900 he established Popular Science Monthly, renamed Scientific Monthly in 1915, which he edited through 1943. His concern with scientific eminence led him to originate, edit, and publish the directory American Men of Science (1906–38). Cattell was dismissed from Columbia in 1917 when he publicly expressed criticism of the draft in World War I. The remainder of his professional life was devoted principally to editing, including The American Naturalist (1907–44) and School and Society (1915–39). In 1921 he founded the Psychological Corporation for the purpose of making research in applied psychology available to industry and business.