The Cannone Guarnerius is a famous violin made by Italian luthier Giuseppe Antonio Guarnieri.

It is also known as the Canon, Il Cannone, or the Cannone del Gesu. Guarneri labelled his instruments Guarneri del Gesù and many of the best and most famous examples are named after musicians or collectors who have at one time owned them. The name "Cannone" was given to this instrument by the Italian virtuoso Paganini.

Paganini lost a highly valuable Amati violin as a result of his penchant for voracious gambling. He was able to take possession of a neglected Guarneri violin, a gift from an amateur violinist and businessman. Paganini played on this instrument for the rest of his life, fondly calling it “my canon violin,” referring to the explosive sound that he was able to make it produce. He bequeathed it to the city of Genoa, Italy upon his death, and it is now considered a national treasure.

When it needed repairs, it was sent to the greatest luthier of the day, Jean Baptiste Vuillaume in Paris. Not only did Vuillaume repair the Guarnarius, but he also made an exact replica. The copy was so precise in every detail of construction and appearance, that not even Paganini could distinguish one from the other. It was not until Paganini noticed subtle differences in tone that he could identify the original. Paganini passed the copy on to his only student Camillo Sivori.

The Cannone and its twin, the Vuillaume copy, are displayed side by side in the Museum of Genoa. They are kept in a good state of repair, and on occasion, Il Cannone is loaned out to musicians for performance. Violin virtuoso Shlomo Mintz performed a special Il Cannone concert on Pagaini’s violin with the Maastricht Symphony Orchestra during the 1990s. In 1999, Eugene Fodor played on the Cannone at a special concert in San Francisco, California. It was the furthest the violin had ever been from Italy. Conditions of its travel included a multimillion-dollar insurance policy and an armed escort of Italian police officers.