The diploma thesis ‚Street Art - Vandalism or Art?' deals with a world-wide phenomenon of contemporary art. The thesis focuses on the characterization of street art and history of street art (its origin and development) and analyzes the difference between street art and graffiti. The thesis presents street art techniques as well as notable street artists. The thesis also observes street art scene in the Czech Republic and depicts features that street art has in common with other art movements of the 20th century as well as with advertising. The diploma thesis will try to answer the question whether street art belongs to art or is pure vandalism. Keywords Street art, graffiti, Banksy, Blek le Rat, Shepard Fairey, vandalism, advertising, art ...