Gissing was educated at Owens College, Manchester, where his academic career was brilliant until he was expelled (and briefly imprisoned) for theft. His personal life remained, until the last few years, mostly unhappy. His two marriages—the first to a prostitute and the second to a servant girl—brought him little but misery, and the life of near poverty and constant drudgery—writing and teaching—that he led until the mid-1880s is described in the novels New Grub Street (1891) and The Private Papers of Henry Ryecroft (1903). In his last years Gissing established a happy relationship with a Frenchwoman, Gabrielle Fleury, with whom he lived.

Before he was 21 he conceived the ambition of writing a long series of novels, somewhat in the manner of Balzac, whom he admired. The first of these, Workers in the Dawn, appeared in 1880, to be followed by 21 others. Between 1886 and 1895 he published one or more novels every year. He also wrote Charles Dickens: A Critical Study (1898), a perceptive piece of literary criticism.

His work is serious—though not without a good deal of comic observation—interesting, scrupulously honest, and rather flat. It has a good deal of documentary interest for its detailed and accurate accounts of lower-middle-class London life. On the social position and psychology of women he is particularly acute: The Odd Women (1893) is a powerful study of female frustration. He did not lack human sympathies, but his obvious contempt for so many of his characters reflects an artistic limitation. Gissing was deeply critical, in an almost wholly negative way, of contemporary society. Of his novels, New Grub Street, considered by some critics to be his only great book, is unique in its merciless analysis of the compromises required by the literary life. Though he rejected Zola's theory of naturalism, his ironic, agnostic, and pessimistic fictions came to be respected for their similarity to contemporary developments in French realist fiction.