The IPG agency will run the integrated advertising, media and digital account out of its London office, with regional support in Germany, France, Hong Kong and Japan.
MullenLowe won the account after a competitive pitch and there is no incumbent on the business.
A fully integrated team will be created for Sloggi comprised of staff from MullenLowe, MullenLowe Open, MullenLowe MediaHub and MullenLowe Profero.
The first work will break later this year for the launch of a new bra range.
The brand's marketing has been quiet in recent years compared to the early 00s, when it hired Olympic champion sprinter Linford Christie to be its brand ambassador and was rapped by the Advertising Standards Authority for placing an outdoor ad featuring bare bottoms near a mosque.
Tom Jacobs, head of marketing strategy at Sloggi said the brand’s aim is to elevate it to the world’s most revered everyday comfort brand.
He said: "[MullenLowe] clearly had a deep understanding of our target consumer and how our brand can become more meaningful to her.
"Strategically, they were able to bring cohesiveness to seemingly diverse elements of the communications programme. We look forward to a great partnership."