August’s match will be played at the 10,000-capacity Racecourse International Stadium in the Sri Lankan capital.
Saints said the country “boasts a rich rugby heritage spanning over 140 years”, with touring sides from England, New Zealand and the British & Irish Lions making stopovers there more than a century ago.
England toured the country in 1971, while the British & Irish Lions visited as part of their tours of New Zealand and Australia in 1930 and 1950.
“This tour symbolizes a revival of that historic connection,” the English club said in a statement.
Saabir Cader, founder and director of the APL, said: “I warmly invite the loyal Saints supporters, the Shoe Army, to visit our beautiful island in August.”
The club said further details for fans wishing to travel to the match would be available “in due course”.