In October, Mediaworks announced that Paul Henry would take over presenting a combined TV and radio breakfast show, that would replace both TV3's Firstline and Radio Live's breakfast.
The new show is likely to start in January or February.
Lush said that though he had enjoyed his eight year stint on breakfast, night time talk was his natural home.
"Newstalk ZB is the pinnacle of talk radio. They are professionals and I can't wait to get started."
Current ZB night host Kerre McIvor will move to afternoons to accommodate Lush, while afternoon host Danny Watson will leave the station at the end of next year to concentrate on his bee business and honey school, Mr Gurney said.
"We are sad to see Danny depart after 15 years with us, the timing works to create something different and exciting in afternoons ...while Marcus' involvement at nights will bring a brand new audience to night-time talk radio."
About Marcus Lush
• Marcus Lush, 49.
• Started his career in the '90s working on TV2's Newsnight with Simon Dallow and Alison Mau.
• In a 2003 episode of Intrepid Journeys, Lush visited Egypt, and in 2004 he produced and presented episodes of train series Off the Rails.
• In 2005 Off the Rails won two Qantas Screen Awards and in 2006 Lush won a NZ Screen Award for best presenter.
• In 2007, he spent a month in Antarctica for the series, Ice.
• He began his radio career on Auckland's student station Radio B (now 95bFM) and in 1989, aged 24, he took on the graveyard talkback shift on 1ZB.
• In the late '90s, he hosted ZM's breakfast show and in 2002 he moved to Southland to host the breakfast show on Foveaux FM until 2004.
• In 2005 he joined Radio Live where he became breakfast host in 2007.