Saints will face Leinster, Ospreys and Castres in next season’s Heineken Cup.
Jim Mallinder’s men were in Tier 2 for the draw which took place in Dublin on Wednesday afternoon.
They pulled out Leinster from Tier 1, meaning the two sides will meet in the competition for the first time since the final in 2011, which the Irish side won 33-22 in stunning circumstances.
Ospreys will provide stiff opposition from Tier 3, with scrum-half Kahn Fotuali’i, who moves to Franklin’s Gardens this summer, set for an immediate reunion with his former club.
Meanwhile, Top 14 champions Castres will hardly be unknown to Saints, with the two sides having faced off in the past three seasons in the pool stages.
“It’s a very tough draw for us, alongside the reigning Pro 12 and Top 14 champions,” said Northampton director of rugby Jim Mallinder.
“Leinster have proved time and again over the past few years that they are one of the top teams in European rugby, with plenty of strength in depth and the ability to play well in the biggest occasions.
“The Ospreys are another top team who have won the Pro 12 twice in the last four years. They have five British Lions in their squad and plenty more Welsh internationals, and Anglo-Welsh clashes in the Heineken Cup are always hard-fought.
“Meanwhile we know that Castres will be as tough as they come. In previous years they have been a difficult team to play, and they will go into next season full of confidence after beating both Clermont Auvergne and Toulon on the way to winning the Top 14 title.
“All six of the matches will be tough challenges, but we will be looking forward to all of them and trying our hardest to get into the knockout stages.”