"The parents went to pick up their daughters after the concert and unfortunately this morning we received news that they did not survive the explosion," Foreign Minister Witold Waszczykowski told the commercial RMF Radio station.
Polish media identified the couple as Angelika and Marcin Klis, quoting social media posts by family members who began searching for them after they went missing on Monday night.
Waszczykowski also confirmed that a third Polish national was injured.
British authorities have identified 22-year-old Salman Abedi, a Briton of Libyan descent, as the perpetrator behind the attack, for which the Islamic State jihadist group claimed responsibility.