Truly hard seltzer maker Boston Beer Co will develop and make the flavoured malt beverage, which will be called 'Hard Mtn Dew'.
The drink will be citrus flavoured and have an alcohol by volume of 5%, the companies said.
"We know that adult drinkers' tastes are evolving, and they are looking for new and exciting flavourful beverages," said Dave Burwick, chief executive officer, Boston Beer.
As recognised leaders in the alcohol and non-alcoholic industries, both Boston Beer and PepsiCo understand the importance of delivering new, break-through innovations to address the changing tastes of drinkers, the company said in a statement.
"The combination of our experience in brewing and developing the best-tasting hard seltzers and hard teas, and MTN DEW, a one of kind multi-billion dollar brand, will deliver the excitement and refreshment that drinkers know and love," Burwick said.
Both companies share the same passion for pushing boundaries and anticipating what consumers want, which has driven decades of bringing ground-breaking, innovative beverages to drinkers in the US and beyond.
"For 80 years MTN DEW has challenged the status quo, bringing bold flavours and unmatched beverage innovation to millions of fans," said Kirk Tanner, CEO, PepsiCo Beverages North America.
"The Boston Beer Company partnership combines two recognised leaders in our respective industries to address the changing tastes of drinkers and we are thrilled at the opportunity to create HARD MTN DEW that maintains the bold, citrus flavour fans know and expect," Tanner added.
The announcement comes at a time when demand for hard seltzer has slowed.