Prosecutors from the southeastern city of Daegu issued a statement saying 13 other people who allegedly financed or offered bribes before betting on illegal gambling sites had also been indicted.
The volleyball players are suspected of deliberately making mistakes when they received, tossed and spiked balls while the baseball pitchers allegedly intentionally allowed walks in the first innings.
The players, who have already been suspended or received lifetime bans, took up to five million South Korean won ($4,450) for each game, according to the prosecution office statement. A total of 23 volleyball and baseball games in 2010 and 2011 were fixed, it said.
Six of the indicated volleyballers are former or current players for the KEPCO45 team, while four others are currently with the military club Sangmu. Two female players from Heungkuk Life Pink Spiders were also among those indicted.
The two baseball pitchers were contracted to the LG Twins based in Seoul before they were expelled from the team over the match-fixing scandal.
South Korea is still reeling from a massive match-fixing scandal that engulfed the domestic football league last year. Almost 80 people have been indicted over the scandal and a former K-League player who was allegedly involved as a gambling broker was found dead in an apparent suicide.
Government officials subsequently threatened to shut down the K-league — Asia's oldest professional football league — if any more games are fixed.
Culture Minister Choe Kwang-shik also promised a zero-tolerance "no mercy" policy on match fixing.
Prosecutors have pinpointed illegal online gambling sites as the root of the problem in South Korea.
Compared with the country's licensed sports lottery that limits the maximum personal bets to 100,000 won ($89), illegal online gambling sites allow people to bet as much as 1 million won ($890), prosecutors say.
It's inexpensive and quick to establish gambling sites which are mostly based overseas to avoid investigation. Investigators said one of the people indicted only spent 8 million won ($7,100) to launch such a site, which typically take about three weeks to establish.
South Korea is one of the most wired countries in the world and its citizens are some of the most Internet-savvy. South Korea has a population of about 50 million people and more than 80 per cent of households have broadband access to the Internet, according to the country's statistical office last year.
The number of online gambling sites has shot up following a government crackdown on unauthorized betting shops across the country in recent years, said Park Jin-kyung, a sports sociology professor at Kwandong University.
"It's a balloon effect," Park said, adding that a lack of sufficient education for athletes at South Korean schools should also blamed.
"We lacked in teaching sportsmanship," he said. "They were only preoccupied with victories and competition."