Rennie will be charged with bringing together several elements of Global Radio's business including its partnership with iTunes, its gaming and directory offerings, CRM and publishing.
In the new role Rennie will also be responsible for developing new commercial digital and broadcast opportunities. He will report to Mike Gordon, managing director, commercial, Global Radio.
Rennie was responsible for developing revenue streams at the high profile video-on-demand offering SeeSaw from September 2009 until last month when he left two months after Bebo-owner Criterion Capital Partners' bought a controlling stake.
Prior to joining SeeSaw, Rennie worked at Channel 4 in a business development and content distribution role. His career also includes stints at Warner Music and Virgin Media.
Gordon said: "This appointment will help drive the business forward, exploiting our radio brands and seeking other commercial opportunities. With over a decade of experience we are absolutely delighted someone of Matt's calibre is joining Global."
Rennie will start at Global Radio on Monday (31 October). He said: "I'm looking forward to starting my new role and working with the dynamic team at Global.
"I'm looking forward to the challenge of developing Global's enterprises."
Follow Maisie McCabe on Twitter @MaisieMcCabe
This article was first published on mediaweek.co.uk