Welter has been brought into the NFC West side for their training camp to serve as a coaching intern for the club's inside linebackers. The 37-year-old previously became the first woman to play in the Indoor Football League as a running back for the Texas Revolution.
Head coach Bruce Arians told the club's official website: "Coaching is nothing more than teaching. One thing I have learned from players is, 'How are you going to make me better?
"If you can make me better, I don't care if you're the Green Hornet, man, I'll listen.' I really believe she'll have a great opportunity with this internship through training camp to open some doors for her."
Welter added on Twitter: "I am honoured to be a part of this amazing team. Special thanks to @BruceArians & the @AZCardinals."
Welter also played for 14 years in the Women's Football Alliance.