The Commish shared the big news prior to the start of the 2021-22 season on Tuesday ... applauding the "great collaboration and cooperation" between the players and players' association.

"Our vaccination rate is incredible," Bettman said. "4 players, not 4% of players. All of our officials are vaccinated. All of the personnel that come into contact with the players are vaccinated."

FYI, there are 32 NHL teams with roughly 23 players on each squad. That's 736 players ... and again, only 4 aren't vaxxed.

Bettman gushes over the whole league's efforts throughout the pandemic ... saying everyone was on board over the past 2 years -- including the bubbles in Toronto and Edmonton, where there was not a single positive COVID-19 test.

"Everybody banded together to do the right thing," Bettman added. "Maybe that's why hockey is the ultimate team sport."

The league is still dealing with some issues surrounding the virus, however -- San Jose Sharks star Evander Kane is reportedly under investigation for allegedly submitting a bogus COVID-19 vaccine card.

On top of that, several Seattle Kraken players were placed in COVID-19 protocol before getting cleared to play in the franchise's first-ever game.