Starting with reproductions from other artists' works, Glenn Brown transforms the appropriated image by changing its colour, position, orientation, height and width relationship, mood and/or size.

However, his exhibition at Tate Britain for the Turner Prize sparked some controversy, as one of his paintings was found to be closely based on the science-fiction illustration "Double Star" created by the artist Tony Roberts in 1973.

Brown appropriates images by living, working artists, such as Frank Auerbach and Georg Baselitz, as well as paintings by historical artists, such as Guido Reni, Diego Velázquez, Anthony van Dyck, Rembrandt, Jean-Honoré Fragonard, Eugène Delacroix, John Martin, Gustave Courbet, Adolph Menzel, Pierre-Auguste Renoir, Vincent van Gogh, Chaïm Soutine and Salvador Dalí.

[16]Brown's paintings, which are uniformly smooth in surface, typically offer a trompe-l'œil illusion of turbulent, painterly application.

Per the artist Michael Stubbs: "Brown‘s computer-based preparation method prior to painting is [not] the sole reason for his relation with the digital.

"[23] The subject matters of Glenn Brown's paintings range from science-fiction landscapes to abstract compositions and figurative images based on art historical references.

[29] Often they are ironically attributed with recurring features such as flowers growing out of their compost-like bodies,[30] hallows placed over heads[31] or red noses.

"[35]His sculptures, deliberately emphasising the three-dimensional quality of oil brushstrokes, stand in stark contrast to his flat paintings.

"[37] In 2008 Brown created a series of prints entitled "Layered Etchings (Portraits)" which were inspired by the artists Urs Graf, Rembrandt and Lucian Freud.

The many contour and incarnation lines of the original works (the artist used up to fifteen different image sources for one layered portrait), as well as the textured spots of lithographic printing, obscure the sitters' individual identities.

Still conceptually rooted to art historical references, he stretches, combines, distorts and layers images to create subtle yet complex line-based works.

Drawing has a freshness and passion painting often doesn’t.”[41]"In drawings produced since 2013, artists of the Renaissance (such as Andrea del Sarto), Mannerism (Bartholomäus Spranger), the Baroque (Peter Paul Rubens), the Rococo (Giovanni Battista Tiepolo), Neoclassicism (Pompeo Girolamo Batoni) and French Romanticism (Eugène Delacroix) have served as starting points for Brown’s eminently variable linear transformations.

The photographer Wolfgang Tillmans won the Turner prize that year, and a legal case brought by Roberts against Brown was settled out of court.

Among them are Gillian Wearing, Abraham Bloemaert, Henri Fantin-Latour, Grace Pailthorpe, Hans Hartung, Austin Osman Spare and Gaetano Gandolfi.