Kaaos was a Finnish hardcore punk band from Tampere, Finland. Formed in March 1980, they were one of the first hardcore punk bands in Finland to release a record. Though their lineup has changed frequently through the years, the band is somewhat active through the years. Only the band's guitarist Jakke (who later became the vocalist) remained as the original member and grew to become the center figure of Kaaos.

Jakke Hallikainen died on 29 November 2007 of alcohol-related causes at the age of 42.

While their early songs became known to be focused on the local authorities (the police) they always criticized not only the government, but also how different beliefs and religions are used to justify war and the suffering war causes. They also sang about day to day violence they had to meet on the street as punks in their day and many other personal topics, yet keeping true to the anarcho punk view.