Brett Favre Uniting Dogs With Veterans, 'It's Saving Their Lives'

Brett Favre's bringing pups to military veterans in need ... and so far, the results have been incredible -- 'cause the NFL legend tells TMZ Sports it's "saving" vets' lives.

The Hall of Famer created the 4 Outdoors program after retiring from football ... and while the plan is to use outdoor experiences to help people in need -- he's found the most success uniting vets with trained service dogs.

"We're connecting them with these dogs and it's saving their lives," Favre says. "It's really incredible."

The dogs aren't just cute as hell -- they're expensive ... coming in at around $50K to get them fully trained up -- and that's where Favre's come in to provide help.

So what now? Brett says it's pretty simple -- check in with the vets in a few months to see what more he can do to help.

"I really believe that we made a positive difference and a positive impact on their lives."