Five of the nine people, including two Turkish and two Uzbek officials involved in communicating live scores to a 'third party', received life bans, the ITU said in its annual report released on Thursday.
Two others had appeals to the Lausanne-based Court of Arbitration for Sport dismissed and their original suspensions upheld.
It was the most cases the TIU, which was set up in 2008, had prosecuted in a calendar year.
The increased workload came after the sport was embarrassed by a report released on the opening day of last January's Australian Open which alleged the unit had failed to deal with widespread match-fixing.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
Tennis authorities at the time rejected the media reports that 16 current or former top 50 players had been repeatedly flagged to the TIU over suspicions they had thrown matches in the past decade.
Philip Brook, who chairs the Tennis Integrity Board that oversees the TIU, lamented in a statement in the annual report that the sport was subject to corruption and promised firm action when it was exposed.
"The issue of betting-related corruption in tennis made 2016 a difficult year for the integrity of our sport," said Brook, who is also chairman of the All England Club.
"It is of course extremely regrettable that corruption exists in tennis.
"While the vast majority of players and officials are beyond reproach, those that choose to abuse the sport should be under no doubt that they will be subject to rigorous investigation, and where proven to have broken the rules, prosecuted."
The TIU reported an increase in the number of alerts they received on suspect gambling behaviour, up to 292 last year from 246 in 2015.
Almost 80 percent (232) of the alerts were generated by matches on the lower tier ATP Challenger and ITF Futures events.
The unit received three alerts in total from the four grand slam tournaments, two from the men's ATP Tour and three from the women's top-tier WTA Tour.
Brook said last January funding would be increased to allow the London-based TIU to hire more staff. The unit doubled its staffing to 10 full-time employees last year.
Funding will also increase by almost 35 percent in 2017, up from $2.4m in 2016 to $3.23m, the report said.
Brook added that the first part of an independent review of the integrity of the sport would be made public later this year.
"We have already committed to accept, implement and fund all of its recommendations," he added.
"In the meantime the TIB, on behalf of all governing bodies, continues to provide unanimous and unequivocal support to the TIU."
(Reporting by Greg Stutchbury in Wellington; Editing by Nick Mulvenney)
