Following in the footsteps of Kerry Katona, the singer and TV presenter, 41, will front a new advertising campaign for the supermarket this year.
His first advert will launch next month.
Iceland's joint managing director Nick Canning said the company was thrilled to land Peter because of his "very high profile with our customers as a singer, presenter, parent and TV personality."
Peter added: "I only ever get involved in a campaign when I truly believe in it... I'm really excited to be working on such a big campaign and looking forward to a great future with the brand."
As a dad, no doubt Peter is more than used to doing the grocery shopping!
Peter is just back in the UK from a holiday to Kenya with fiancee Emily MacDonagh, 25, and his children Junior, Princess and baby Amelia.
He was spotted back at work at the ITV studios yesterday, filming voiceovers for his 60 Minute Makeover series, and will hit the road in September for a 24-date tour in support of his Big Night album.
Watch Peter's 'Big Night' video below: