George Robert Sims (2 September 1847 – 4 September 1922) was an English journalist, poet, dramatist, novelist and bon vivant.

In the 1870s Sims began writing lively humour and satiric pieces for Fun magazine, of which he became editor, and The Referee, his light verses from which sold separately and remained popular for decades. He was soon concentrating on social reform, particularly the plight of the poor in London's slums, which helped to bring about reform legislation. He also founded a charity to fund free school meals in London. A prolific journalist and writer he also produced a number of novels, a volume of reminiscences, writings on leisure and travel, and detective stories.

Sims wrote more than 30 plays, often in collaboration, several of which had long runs, tours and international success. During a tour of one of them, however, the Exeter Theatre Royal burned down, killing 186 people. He bred bulldogs, was an avid sports enthusiast and had a large circle of literary and artistic friends. By the time of his death, he had gambled most of his substantial fortune away. The Times wrote in Sims's obituary that

"so attractive and original was the personality revealed in his abundant output—for he was a wonderfully hard worker—that no other journalist has ever occupied quite the same place in the affections not only of the great public but also of people of more discriminating taste.... Sims was indeed a born journalist, with the essential flair added to shrewd common sense, imagination, wide sympathies, a vivid interest in every side of life, and the most ardent patriotism.... He was [also] a highly successful playwright... a zealous social reformer, an expert criminologist, a connoisseur in good eating and drinking, in racing, in dogs, in boxing, and in all sorts of curious and out-of-the-way people and things."