The issue will include information on celebrity Sport Relief fundraising activities by personalities including James Corden, Denise Van Outen and David Walliams, who led the BT Sport Relief Million Pound Bike Ride.
The IPC Media owned title will donate 5p from the sale of every copy to the charity.
Walsh visited Uganda for Sport Relief to see how the money she raised by climbing Mount Kilimanjaro last year for the charity were being used.
A film of her fundraising journey will air between 19 and 21 March during Sport Relief Weekend.
Walsh is also the guest commentator on Now’s ’The Week In Outfits’ column.
Sport Relief has also teamed up with Microsoft search engine Bing.com to launch the ’Bing Search Mile’, a virtual fundraising initiative that lets internet users raise money for Sport Relief by searching using Bing.
For every 10 searches made, Bing will donate 5p to Sport Relief.