George Chetwynd Griffith-Jones (20 August 1857 – 4 June 1906) was a British writer. He was active mainly in the science fiction genre—or as it was known at the time, scientific romance—in particular writing many future-war stories and playing a significant role in shaping that emerging subgenre. For a short period of time, he was the leading science fiction author in his home country both in terms of popularity and commercial success.

Griffith grew up with his parents and older brother, receiving home-schooling and moving frequently during his childhood due to his father's career as a clergyman. Following his father's death when Griffith was 14 years old, he went to school for little over a year before leaving England and travelling the world, returning at the age of 19. He then worked as a teacher for ten years before pursuing a career in writing. After an initial setback that left Griffith without the means to provide for himself, he was hired by the publisher C. Arthur Pearson in 1890. Griffith made his literary breakthrough with his debut novel The Angel of the Revolution (1893), which was serialized in Pearson's Weekly before being published in book format. He signed a contract of exclusivity with Pearson and followed it up with the likewise successful sequel Olga Romanoff (1894).

Griffith was highly active as a writer throughout the 1890s, producing numerous serials and short stories for Pearson's various publications. He also wrote non-fiction for Pearson and went on various travel assignments. Among these were an 1894 publicity stunt in which he circumnavigated the world in 65 days, an 1895 journey to South America where he covered the various revolutionary movements active there at the time, and an 1896 trip to Southern Africa that resulted in Griffith writing the novel Briton or Boer? (1897) anticipating the outbreak of the Boer War (1899–1902). Griffith's career declined in the latter part of the 1890s, and he was surpassed by H. G. Wells as the favourite science fiction writer of both Pearson and the reading public. His last outright success was A Honeymoon in Space (1901), and he parted ways with Pearson shortly thereafter. With his health in decline, likely due to alcoholism, he continued writing prolifically up until his death at the age of 48.

Griffith was both successful and influential as a writer at the peak of his career, but he has since descended into obscurity. Retrospective assessments have found his works to have been timely and prescient—in particular with regard to the importance of aerial warfare—but not timeless, and he is commonly regarded as a relatively poor writer, especially when compared to his main rival, Wells. He regularly incorporated his personal viewpoints into his fiction, and anti-American sentiments expressed in this way ensured that he never established a readership in the United States as publishers there would not print his works. He was irreligious and in his youth advocated fiercely for secularism. Politically, Griffith was early an outspoken socialist, though he is believed to have gradually shifted towards more right-leaning sympathies later in his life. Socially, he has been described as embodying Victorian ideals, including social conservatism and staunch pro-British views.

George Chetwynd Griffith-Jones was born in Plymouth, Devon, on 20 August 1857. His parents were the clergyman George Alfred Jones and Jeanette Henry Capinster Jones. The family, which also included Griffith's older brother, moved repeatedly during his childhood due to his father's career. They moved from Plymouth to Tring, Hertfordshire, in 1860, then on to two poverty-stricken parishes in the Greater Manchester area: first to Ashton-under-Lyne in 1861, and then to Mossley, where his father was appointed vicar in 1864.

As the family's financial situation did not allow for the formal education of two sons, Griffith was home-schooled, with his mother teaching him French and his father Latin and Greek. He also spent considerable time exploring his father's extensive library, which was filled with the works of authors who would later serve as Griffith's literary influences, including Walter Scott and Jules Verne. Following the death of his father in January 1872, he started studying at a private school in Southport at the age of 14. There the limits of his home-schooling soon became apparent, the lack of any mathematical proficiency in particular, but through concerted effort he progressed to being the second-best pupil in his class.

Then I went to another school, or perhaps I should put it more correctly if I said that I matriculated in the greatest of all universities—the world. I went to sea as an apprentice on a Liverpool lime-juicer ... In the seventy-eight days between Liverpool and Melbourne I learnt more of the world than I had learnt in fourteen years, but the methods of tuition didn't suit me. The learning was hammered in a little too hard, mostly with a rope's end and the softest part of a belaying pin, so I took French leave of that class-room and went to another; in plain English, I ran away from my ship and went up in the bush.

Griffith left the school after 15 months, out of economic necessity—his father had left behind less than £300, all of which went to his wife in the absence of a will—and joined a sailing ship as an apprentice at the age of 15. He deserted his ship in Melbourne after 11 weeks at sea, having found the experience highly instructive but the corporal punishment in particular gruelling. He then took various employments in Australia—chiefly manual labour, but also briefly serving as a tutor—before using his earnings to travel. He later claimed both to have received an offer to marry a Polynesian princess and to have circumnavigated the globe six times; about the latter, the science fiction historian Sam Moskowitz says that "the variety of locales for his stories would tend to substantiate this claim." He returned to England at the age of 19.