Robert James Graves FRCS (27 March 1796 – 20 March 1853) was an Anglo-Irish surgeon after whom Graves' disease takes its name. He was President of the Royal College of Physicians of Ireland, Fellow of the Royal Society of London and the co-founder of the Dublin Journal of Medical Science. He is also claimed to be the uncredited inventor of the second-hand on watches.

The eighth child of the Dean of Ardagh, Richard Graves, and Elizabeth Mary Drought (1767–1827), daughter of Rev. James Drought (1738–1820) D.D., of Dublin and Park, "a member of one of the principal families of the King's County (Offaly)," whose mother was the sister of Theaker Wilder. Wilder, Robert's father and maternal grandfather were all Senior Fellows of Trinity College Dublin, where in 1811 he was entered under his elder brother-in-law, Thomas Meredith, after receiving his early schooling in Downpatrick and Dublin.

After a brilliant undergraduate career in the arts, he received a degree in medicine in 1818 and left for London to study surgery under Sir William Blizard. Afterwards, he spent the following three years travelling the continent between stints as an observer at the medical schools of Edinburgh, Berlin, Vienna, Göttingen, Hamburg, Copenhagen and those of France and Italy.

Graves had an exceptional talent for languages, and while in continental Europe he was imprisoned for ten days in Austria when travelling on foot without a passport; the authorities thought him to be a German spy, none of them believing that an Irishman could speak their language so well. Continuing his travels, in the Swiss Alps Graves became acquainted with the painter Joseph Mallord William Turner. They travelled and sketched together for several months, eventually parting company in Rome. On his way from Genoa to Sicily, Graves saved a ship and its mutinous crew by assuming command during a storm in the Mediterranean. During a gale the vessel sprang a leak, the pumps failed, and the crew attempted to abandon ship: Graves holed the one lifeboat with an axe, declaring to the crew, "let us all be drowned together, it is a pity to part good company", he then proceeded to repair the pumps with leather from his own shoes, so saving the ship and all aboard.

Graves returned to Dublin in 1821, setting up his own medical practice and introducing new clinical methods that he had witnessed on his travels to the Meath Hospital and the Park Street School of Medicine which he helped found. This included, among other things, bedsides teaching, of which William Hale-White said "this is real clinical teaching", and went on in his book, Great Doctors of the Nineteenth Century, to say that Graves held the honour of introducing this system to Ireland:

(Graves) insists that... mere walking the hospital must go. The Edinburgh system, in which the teacher interrogates the patient in a loud voice, the clerk repeats the patients' answer in a similar voice, the crowd of students round the bed, most of whom cannot see the patient, hears all this and makes notes, is of no use. Students must examine patients for themselves under the guidance of their teachers, they must make suggestions as to diagnosis, morbid anatomy and treatment to their teacher who will discuss the cases with them.

In this technique one of his students, William Stokes (1804–1878), soon became his collaborator. Together they made the Dublin School of Medicine famous throughout the world.

Graves was possessed of the qualities that would ensure a great teacher. He was tall, somewhat swarthy with a vivacious manner, and like other avant-garde professors of his time, he gave his lectures in English rather than in Latin, or Dog Latin as was still the case in most classes in the 1830s. In his introductory lecture he said: "From the very commencement the student should set out to witness the progress and effects of sickness and ought to persevere in the daily observation of disease during the whole period of his studies".