The deal was signed on Friday at the 23rd Tactical Aircraft Base in Minsk Mazowiecki near Warsaw, with President Andrzej Duda in attendance.
"It is yet another historic day as new prospects are opening up for the Polish Armed Forces," Blaszczak said at the ceremony.
The FA-50s will replace the old Soviet-era MiG-29 fighter jets, which Blaszczak called "a generational leap".
"The contracts also include a training package with link trainers, simulators and a logistics package," Blaszczak said. "We've also agreed to build a service centre in Poland based on cooperation between Korea Aerospace Industries and Polish Armaments Group.
According to the defence minister, the new planes will patrol skies over Poland and other Nato states.
Blaszczak said in July that the decision to buy three squadrons of the FA-50s was based on recommendations from Polish military pilots. The aircrafts are light and multi-functional and are based on the US-made F-16 fighters Poland already uses, so the infrastructure can be adapted seamlessly. He added that the FA-50 is an ideal aircraft to train pilots to fly the F-16 and that they would need just a few hours to adapt to the latter.
According to Blaszczak, the first FA-50 planes will be delivered in 2023 and will have Korean configuration. The next 36 aircraft will be adapted to the requirements of the Polish Air Force and will be delivered at a later date. (PAP)