The money will be used to buy gym equipment to help teach underprivileged children and young adults living in Guaruja Brazilian jiu-jitsu and mixed martial arts.
Poirier made the donation to The Charles Oliveira Institute through his own non-profit The Good Fight Foundation which is based in his hometown of Louisiana.
The Diamond is not short of a bob or two having banked over $2 million following back-to-back victories over Conor McGregor last year.
And now he has handed over some cash through his foundation to help those in need.
On Instagram he wrote: “Promise made promise kept.
“We are supporting Charles and his mission to empower the youth of Brazil.
All the best to you in your upcoming title defence.”
Oliveira also confirmed Poirier’s charitable donation on Friday.
He wrote in reply: “Thank you very much Diamond.
“Your help is so important.
“Thank you for the love, Dustin Poirier.
“No words to describe how I appreciate your help and it will be key to helping underprivileged kids’ lives.”
Oliveira’s foundation was set up in 2021 and has a special focus on helping children and youths who may be disadvantaged stay away from a life of crime.
Poirier, 33, said he felt compelled to help out his former opponent after watching footage of Oliveira’s tough upbringing on the streets of Brazil.
He previously said: “I saw a video this week of him showing where he grew up and where his mom cooked dinner for him. I think it was an old video.
“I saw some of the sights of where he grew up and just how little they had, it came to me this week.
“I thought I was going to let him know win, lose or draw, talk to him after and let him know me and the Good Fight Foundation would donate $20,000 to his city in Brazil and put the money to wherever he thinks it needs to be.
“He’s a good guy and he knows where the money will go the furthest, that’s what we’re going to do.
“And like I said, man, I’m going to continue to try to do good and that’s it. I want to be a better person every day.”