The Los Angeles Times reported Buss, 79, is being treated for an undisclosed form of cancer. Current and former Lakers players -- including Bryant, Pau Gasol and Magic Johnson -- have visited Buss at Cedars-Sinai Medical Center in Los Angeles.
A team spokesman said the Lakers do not plan to discuss Buss' health, the Times said.
Bryant spoke about Buss in Houston, where he is participating in the NBA All-Star weekend.
"He's meant everything to me in my career in terms of taking a risk on a 17-year-old kid coming out of high school and then believing in me my entire career," Bryant said at a news conference. "And then for the game itself, the brand of basketball that he implemented in Showtime carried the league."
Bryant -- acquired by the Lakers in a trade with Charlotte -- has played on five NBA championship teams and been to the finals seven times with the Lakers.
He said Buss' impact on basketball is "beyond measure. There's nothing you can do to really define it. What he's done consistently, it's tough to really find a match for that in any sport. He's been a model of consistency."