Carnival of Ovar (European Portuguese: [kaɾnɐˈval dɨ oˈvaɾ]) is a major Portuguese tourist event that takes place in Ovar, in the Aveiro Region.

Because it attracts thousands of visitors every year, it eventually became the trademark event of the city.

[4] While the Ovar Carnival Celebrations are first mentioned in local newspapers, as early as the late 19th century, a more similar version of the current event was established around the 1950s, the so-called "Dirty Carnival".

It consisted in a "dirty battle", using flour, eggs, dust or soot.

Eventually, all Ovar neighborhoods joined the competition, and its popularity started to attract an increasing number of tourists.