Harald Naegeli (born 4 December 1939) is a Swiss artist best known as the "Sprayer of Zurich" after the graffiti he sprayed in the late 1970s onto walls and buildings in Zürich, Switzerland.

He evaded the trial by fleeing to Germany to his confidant, journalist and author Hubert Maessen, yet was sentenced in absentia to nine months in jail and a fine of CHF 206,000.

In Germany, his work was more appreciated as art, and Naegeli remained there for the next few years and became acquainted with Joseph Beuys, who was a neighbor of Maessen in the city of Düsseldorf.

Naegeli continued to spray his characteristic wireframe graffiti in Cologne and Düsseldorf, and although they were not unanimously welcomed there either they caused much less discussion than they had in Zürich.

In Cologne, he produced in 1980/81 a cycle of about 600 graffiti that became known as the Kölner Totentanz; most of these works were removed already the day after their creation by the city cleaning department.

Adolf Muschg, an eminent Swiss writer and later professor for literature at the ETH in Zürich and one of the 72 artists who had signed the petition, commented later: "He doesn't work on commission.

On 29 April 1984 Naegeli turned himself in to the Swiss police at the border crossing in Lörrach and subsequently served his jail sentence.