Karunaratne has signed a deal at Headingley to play in the next three LV= Insurance County Championship games.
The 33-year-old scored a century against India last month, the 14th of a career that has seen him amass 5,620 Test runs.
But there is no place in the White Rose squad for former England skipper Joe Root as he is being rested after a busy winter of Test cricket.
Yorkshire will still include plenty of players with England experience though, with Dawid Malan, Dom Bess, Matthew Fisher, Adam Lyth and Harry Brook all set to feature.
Former Northants all-rounder David Willey won't be involved as he is playing in the Indian Premier League, as is another England man in Jonny Bairstow.
Northants have yet to name their side, but head coach John Sadler has a fully fit squad to pick from. The County are expected to hand debuts to overseas pair Will Young and Matt Kelly.
Yorkshire squad to play Northants: Dom Bess, Harry Brook, Harry Duke (WK), Matthew Fisher, George Hill, Dimuth Karunaratne, Tom Loten, Adam Lyth, Dawid Malan, Steven Patterson ©, Haris Rauf, Matthew Revis, Jordan Thompson, James Wharton.