The league formed in 1973 with six teams from the Chūgoku region: Mazda Auto Hiroshima SC, Hiroshima Teachers, Mitsui Shipbuilding Soccer Club, Mitsubishi Oil, Mitsui Oil and Hitachi Works Kasado SC. The format was in a round-robin tournament with teams playing each other twice; once at home and once away. Winning teams earned two points, one point was given to each team in a draw, and losing teams earned no points. League position was determined by the number of points. The following season, the number of teams increased to eight and generally stayed at that number for some time. However the Mitsui Oil team withdrew from the competition in 1975 because of an oil spill accident at their parent company, leaving the league with seven teams briefly. In the late 1980s, Kawasaki Seitetsu Mizushima SC and Mazda Auto Hiroshima SC achieved promotion to the then Japan Soccer League. Although Kawasaki Seitetsu Mizushima SC were able to avoid relegation back to the Chūgoku League, Mazda Auto Hiroshima SC were relegated the season following promotion twice. In 1991 the league format changed, awarding three points for a league win, rather than just two. From 1997 a penalty kick system was introduced so matches could be firmly decided instead of having a draw. If at the end of 90 minutes the game ends in a draw, a penalty shoot out is held. The winning team is awarded two points and the losing team is awarded one point. In the 2000s, SC Tottori, Mitsubishi Motors Mizushima F.C. and Fagiano Okayama achieve promotion to the JFL. From 2007 the penalty kick system ended, and standard regulation matches commenced. Teams played each other at home and away, and an appropriate method was decided in order to determine league placements should teams have the same number of points. Based on those results, the top four teams would be split from the next four teams. Teams would play in these smaller groups against each other once, meaning the final league result is based on 21 matches. Furthermore, this means that teams finishing 9th or 10th will not be able to have the chance at promotion after the initial 18 matches, should they situation arise. Since 2008, the league has consisted of ten teams. In 2009, the two block split was abolished, and a traditional home and away league structure was introduced.
Regulations
Just like the JFL, matches last for two 45 minute halves with no extra time. Winning teams receive 3 points, drawing teams receive one point, and losing teams receive no points. League winners earn the right to represent the Chūgoku region at the Regional League promotion series, with the aim of promotion to the JFL. Depending on the year, two or more teams may also be invited.
Participating teams
2015 season
These are the ten participating teams in order of their final position in the previous season.
Basically, for the league champions to be promoted to a higher league, it is necessary to compete in a specified national tournament. Up until and including the 1976 season, the All Japan Senior Football Championship was used in which the winner and runner-up played off in a promotion and relegation series against the bottom two clubs of the JSL. However, from 1977 the Regional League promotion series became the tournament of choice. The following teams have achieved promotion from the Chūgoku Soccer League.
The top two teams from each of the five prefectural leagues in the Chūgoku region meet in a promotional tournament. Teams are split into two blocks, with the block winners being promoted to the Chūgoku Soccer League. However, owing to which teams are promoted to and relegated from the JFL, there is a possibility that the number of promotions from the Prefectural leagues will change.
Relegation to the Prefectural Leagues
The two teams positioned 9th and 10th at the end of the season are relegated to their local Prefectural League.
Final league positions
Teams in blue participated in the National Promotional Tournament, with bold teams achieving promotion.