AC卡亚尼

AC Kajaani was founded in 2006 by a merger of Kajaanin Palloilijat (KaPa -- "Kajaani Ballers") and FC Tarmo. The newly merged club took over FC Tarmo's place in the Kolmonen—the fourth tier of the Finnish soccer league system—in the Northern Finland group. Arvo Toivainen was the chairman of the club. Only KaPa's adult men's team joined the new club; KaPa continued to operate their own youth clubs, with an affiliation with the new club. However, KaPa would eventually cease its youth football operations, which would not restart until 2014.

In the club's first four seasons, the club managed to finish in second place on all four occasions, missing out on promotion by small margins each time, including on goal difference in 2009 to city rival Kajaanin Haka.

In 2011, AC Kajaani finally won its long awaited league title, earning promotion to the Kakkonen, in the Pohjoinen (Northern) group. The season was special for AC Kajaani as they completed an undefeated season, finishing with a league record of 17 wins and one draw, while winning once and drawing once against JPS in a 5–2 aggregate victory in the playoffs. Kajaani won the league title in its first year in the Kakkonen and defeated JäPS in the playoffs to earn a second straight promotion, to the Ykkönen, the second tier of the Finnish soccer league system.

In 2013, AC Kajaani endured a poor year in the Ykkönen, winning only three matches all season long, while earning a relegation back down to the Kakkonen. Back in the Kakkonen, AC Kajaani finished third in three consecutive seasons. A highlight from the 2016 season was AC Kajaani's deep run in the Suomen Cup, where they made it to the sixth round and hosted HJK, Finland's top football club, and took them to extra time, ultimately losing 5–1 in front of a club record 1,172 spectators. In 2017, Kajaani won the league title for Group C and winning the promotion playoffs against KTP.

In 2018, AC Kajaani experienced its most successful season, finishing in 8th place with 25 points while winning six matches and remaining in the Ykkönen for the following season, a feat Kajaani would repeat in 2019 with another 8th place finish and 24 points.

In 2020, AC Kajaani renewed its partnership with KaPa Kajaani, who agreed to become the official youth team of AC Kajaani. In exchange for the new partnership, AC Kajaani agreed to change its colours from white and black to KaPa's traditional colours of blue and white.

In 2020, Kajaani planned for a large push to make it to the Veikkausliiga and spent €274,819 on player wages, second in the league. However, AC Kajaani's luck would run out when they were relegated on the final day of the season by Gnistan, despite winning their final match against KTP by a score of 4–1. Erfan Zeneli scored the club's final goal.

Following the 2020 season, chairman Arvo Toivainen announced that while the club was debt-free, he no longer had the ability to fund the club, having spent €1.7 million on the club thus far, including €250,000 in 2020 alone. He required a further investment of €350,000 from AC Kajaani's business partners in order to get the club back up to the Ykkönen, and upon receiving commitments for only €100,000, the decision was made to fold the club and cease operations. Following the fall of the club, criticism was made of the club's attempts to buy a quick path to success by importing foreign players, as opposed to investing in building up local talent; only Tatu Hoffrén was from Kajaani.