The 32-year-old fullback made 60 appearances in Brumbies colours from 2012 to 2015 and made his Wallabies debut against the British and Irish Lions in 2013.
Mogg spent three years at French club Montpellier, winning the European Challenge Cup in 2016 alongside Nic White before moving within the Top 14 League to Pau.
Mogg’s addition will bring experience to the Brumbies outside backs where he will join current Wallabies squad members Tom Banks, Andy Muirhead and Tom Wright who are all returning from the 2021 Brumbies playing group.
Jesse Mogg said: “I’m delighted to be returning home to Australia with the Brumbies.”
“I’ve obviously kept an eye on how the team has been going since I’ve been away and I’ve been impressed with how they've continued to grow a strong culture and success on the field and I’m excited to be a part of the Brumbies again.
“Having a few familiar faces still at the club like Dan, Laurie and Whitey of course, will make it easier for me to transition back and I’m just really excited to rip into preseason.”