Umbro will manufacture the Ospreys' kit from next season.
The Welsh region have agreed a five-year deal with the sportswear company, ending a four-year partnership with Canterbury.
Starting next season, Umbro will provide the region with its matchday kit, training range and leisurewear. These will include men's, women's and children's ranges.
It sees the Ospreys join the likes of England and Bristol Bears in Umbro's rugby portfolio.
“We have always prided ourselves on being forward thinking and this new partnership is an example of the Ospreys philosophy and ambition to embrace and explore new markets and audiences," said the region's new chief executive Nick Garcia.
"In Umbro we have found a partner with a shared ambition for innovation and diversification.
“The Ospreys are excited to be amongst other high-performance teams in Umbro’s portfolio and we look forward to collaborating on more than the traditional first team jersey.
“This journey will start with high performance training and matchday apparel before developing a new lifestyle range targeted at a younger audience and the traditional loyal base of Ospreys rugby supporters.”
Sam Lucas, Director of Sports Marketing, Umbro added: “Today’s announcement is incredibly exciting for Umbro. Ospreys are Wales’ most successful region and we are proud to partner with them as they embark on a new strategic direction.
"We will be taking great pride in developing a jersey that will represent the club and its supporters both in the heartlands of Welsh rugby, and globally."
