Sagan is a coined word with a couple of meanings behind it. One of its homophones is sandstone(砂岩,sagan?) in Japanese. This symbolises many small elements uniting to form one formidable object. Also, Sagan Tosu can be interpreted as "Tosu of Saga (Prefecture)" (佐賀ん鳥栖,Saga-n Tosu?) in the area's dialect. In addition, it is widely believed that the word is meant to be a pun with Italian giants Juventus although the club hasn't confirmed it.
In February 1997, Sagan was established as a new club which virtually takes over Tosu Futures, which became insolvent in the previous month, and admitted to participate Japan Football League from 1997 to 1998, as well as J. League Cup in 1997 as a preferential measure, although J. League Associate Membership status is not awarded to Sagan. In 1999 they were admitted to the new J. League Division 2 (J2) as the original ten teams, where they remained until their promotion to J1 at the end of the 2011 season.
In their first season at the J. League Division 1 in 2012, confounding the prediction of many critics about their immediate relegation to J2, they have been maintaining their position between 5th and 11th places all the way through the season, only except after the 2nd week in which they were ranked as 13th. They were ranked third after the 33rd week, having a chance to qualify to 2013 AFC Champions League if they would not lose to Yokohama F. Marinos in the last match of the 2012 season. However, they have lost to Yokohama by 0-1 then ended up as 5th, while Urawa Red Diamonds defeated Nagoya Grampus and ranked as 3rd.
In 2014, the club have been in the most successful season in J. League Division 1, as being ranked on the top of 2014 J. League Division 1 after the 1st, 2nd, 13th, and 18th week. However, the club made an announcement on 8 August, several days after the 18th week match when Sagan moved back to the top of the league, to terminate the contract with the head coach Yoon Jung-Hwan as of 7 August all by sudden.
17Sakata Michitaka - A former professor of Saga University and the person which backed up in both the establishment of Tosu Futures and the team's revival as Sagan Tosu. He died due to kidney cancer on January 7, 2000. The number 17 indicates his day of death.