The three-year deal kicks off on January 1.
Intersport’s investment will assist with the establishment of new parkrun events, while supporting existing event teams with essential kit.
The retailer will also be providing exclusive offers to parkrun’s 1.3 million UK participants.
Intersport UK general manager Tom Foley says: “parkrun has been a key player in promoting running as an accessible participation sport to the expanding community of runners.
“The parkrun model of local volunteers delivering weekly runs to people of all ages and abilities in their local community fits perfectly with the Intersport philosophy.
“We are excited to see this partnership come to life and develop these running communities further together – encouraging more people to get their running shoes on.”
parkrun UK currently organises free timed runs at more than 400 locations every weekend.