The deal means the retailer is now the official sportswear partner for the event which attracts 680,000 participants each year, until 2012.
It will promote the event in-store and via its online communications in addition to developing the bespoke range. Reebok was previously the former official apparel and training partner.
The retailer has appointed PMA Marketing to create an online campaign to support the partnership which will see participants encouraged to send video messages of thanks to their sponsors.
Race for life is the largest women only fundraising event in the UK which this year features over 230 events taking place around the country between May and July.