Thomas Ruff (born 1958 in Zell am Harmersbach) is an internationally renowned German photographer who lives and works in Düsseldorf.

During his studies in Düsseldorf, Ruff developed his method of conceptual serial photography. His initial main topic was the interior of German living quarters, with typical features of the 1950s to 1970s (room portraits and design details). This was followed by similar views of buildings and portraits of friends and acquaintances. These are typically shown with emotionless expressions, in very large, passport-style portraits of great detail and high resolution. In a discussion with Philip Pocock (Journal for Contemporary Art, 1993), Ruff mentions a connection between these portraits and the police observation methods in Germany in the 1970s during the German Autumn.

Thomas Ruff's building portraits are likewise serial and reclusive, and have been edited digitally to remove obstructing details – a typifying method, which gives the images an exemplary character (Ruff: "This type of building represents more or less the ideology and economy in the West German republic in the past thirty years"). The photographic method was also standardised, regarding light, perspective and location.

These series were followed in 1989 by images of the night sky, which were not based on photographs by Ruff. In the years from 1992 to 1995, Ruff produced night images (of exteriors and buildings), with a night vision device, which apparently was deliberately used in analogy to military and espionage applications. In 1994 to 1996 these were followed by Stereoscopy images. A further series in the 1990s consists of "Newspaper Images"; here Ruff again utilised others' pictures in a similar fashion to his night sky images. He used newspaper clippings enlarged without their original subtitles.

In 2003 Thomas Ruff published a photographic collection of "Nudes" with a text by the French author Michel Houellebecq. Ruff's images here are based on Internet pornography, which was digitally processed and obscured. This series was received very ambivalently.