Theory of Colours is a book by Johann Wolfgang von Goethe about the poet's views on the nature of colours and how they are perceived by humans. It was published in German in 1810 and in English in 1840. The book contains detailed descriptions of phenomena such as coloured shadows, refraction, and chromatic aberration. The book is a successor to two short essays titled "Contributions to Optics".

Johann Wolfgang von Goethe was a German polymath and writer, who is widely regarded as the greatest and most influential writer in the German language. His work has had a profound and wide-ranging influence on Western literary, political, and philosophical thought from the late 18th century to the present day. Goethe was a German poet, playwright, novelist, scientist, statesman, theatre director, and critic. His works include plays, poetry and aesthetic criticism, as well as treatises on botany, anatomy, and color.