Szczesny, 34, spent seven seasons at Juve and had one year left on his contract. He had been linked with a move to fellow Italian side Monza and Saudi Pro League club Al-Nassr.
Having started his career at Premier League club Arsenal, Szczesny won the Serie A title three times with Juventus as well as the Coppa Italia on three occasions. He also had loan spells at Brentford and Roma.
Wojciech Szczesny saves a penalty kick by Argentina's Lionel Messi during the 2022 World Cup. (AP PHOTO)
He played 84 times for Poland.
"I left Warsaw, my hometown, in June of 2006 to join Arsenal with one dream — to make a living out of football," Szczesny posted on Instagram. "Little did I know it would be a start of a journey of a lifetime.
"Everything that I have and everything that I am I owe to the beautiful game of football.
"But I also gave the game all I had. I gave the game 18 years of my life, everyday, without excuses. Today, though my body still feels ready for challenges, my heart is not there anymore.
"I feel that right now it is time to give all of my attention to my family."