The NBA legends sat down with "Shark Tank" star Daymond John for Black Entrepreneurs Day -- to talk to young people about the importance of financial intelligence.

And man, if these stories don't get the point across ...

Shaq says he was so uneducated about finances when he signed his first endorsement deal after turning pro, he blew $1 MILLION in an HOUR -- splurging on expensive cars, jewelry and a trip to Vegas.

In fact, he went through so much cash, his bank manager pulled him aside and warned him that he was gonna go broke if he continued to spend like a maniac ... because he wasn't accounting for things like income tax, etc.

Dwyane Wade tells a very similar story -- saying he got tangled up in some bad investments because he had no idea what he was doing.

"I blew through a lot of money," Wade said ... "I got into bad relationships with people from ... ventures outside of basketball, restaurant ventures, etc."

Wade says he simply wasn't educated when it came to finances -- and had to learn the hard way after being taken advantage of.

But now, both superstars are hoping their loss can be your gain -- stressing the importance of financial intelligence so young people spend their money wisely and make it last a very long time.