In science fiction, hyperspace (also known as nulspace, subspace, overspace, jumpspace and similar terms) is a concept relating to higher dimensions as well as parallel universes and a faster-than-light (FTL) method of interstellar travel. Its use in science fiction originated in the magazine Amazing Stories Quarterly in 1931 and within several decades it became one of the most popular tropes of science fiction, popularized by its use in the works of authors such as Isaac Asimov and E. C. Tubb, and media franchises such as Star Wars.

One of the main reasons for the popularity of the concept is the impossibility of faster-than-light travel in ordinary space, which hyperspace allows writers to bypass. In most works, hyperspace is described as a higher dimension through which the shape of our three-dimensional space can be distorted to bring distant points close to each other, similar to the concept of a wormhole; or a shortcut-enabling parallel universe that can be travelled through. Usually it can be traversed – the process often known as "jumping" – through a gadget known as a "hyperdrive"; rubber science is sometimes used to explain it. Many works rely on hyperspace as a convenient background tool enabling FTL travel necessary for the plot, with a small minority making it a central element in their storytelling. While most often used in the context of interstellar travel, a minority of works focus on other plot points, such as the inhabitants of hyperspace, hyperspace as an energy source, or even hyperspace as the afterlife.

The term occasionally appears in scientific works in related contexts.