"I am no longer in government. Prime Minister Mateusz Morawiecki and, as far as I know, President Andrzej Duda accepted my resignation," Kaczynski said, as quoted by state-run Polish news agency PAP.
According to Kaczynski, he now intends to devote his free time to working in the party and preparing for parliamentary elections.
Kaczynski has been at the helm of the PiS party since 2003. After being re-elected as party leader last summer, he said he would not run for the post again.
Kaczynski is the twin brother of Polish President Lech Kaczynski, who died in April 2010. In July 2010, he took second place in the Polish presidential election, losing to Bronislaw Komorowski.