Larry Niven is known as an author for his hard science fiction, using big, but authentic scientific concepts and theoretical physics. His Known Space series is one of the most popular "future history" sagas in SF and includes the epic novel Ringworld, one of the few novels to have won both the Hugo and Nebula awards, as well as the Locus and Ditmar awards, and which is recognized as a milestone in modern science fiction.

Niven also often includes elements of detective fiction and adventure stories. His fantasy includes his The Magic Goes Away series, which utilizes an exhaustible resource, called mana, to make magic a non-renewable resource. Niven created an alien species, the Kzin, which were featured in a series of collections, the Man-Kzin Wars. He co-authored a number of novels with Jerry Pournelle. In fact, much of his writing since the 1970s has been in collaboration, particularly with Pournelle, Steven Barnes, Brenda Cooper, or Edward M. Lerner. His Beowulf’s Children, co-authored with Jerry Pournelle and Steven Barnes, was a New York Times bestseller.

He has also written for the DC Comics character Green Lantern, including in his stories hard science fiction concepts such as universal entropy and the redshift effect, which are unusual in comic books, as is his "Man of Steel, Woman of Kleenex," a memorable if not-quite-serious essay on Superman and the problems of his having a sex life.

He has received the Nebula Award, five Hugos, four Locus Awards, two Ditmars, the Prometheus, and the Robert A. Heinlein Award, among other honors. Most recently, the Science Fiction and Fantasy Writers of America have presented him with the Damon Knight Memorial Grand Master Award, given for Lifetime Achievement in the field. He lives in Chatsworth, California.