"I think this is the right thing to do," the 38-year-old said. "Some time has passed since the end of the [Serie A] championship but I needed to reflect a bit.
"Now that my career is finished I can say that I am happy with what I have achieved."
He added: "Not everyone can say that they set themselves an objective and reached it – I did that and it is very satisfying."
Zola, who ended his career with Cagliari, made his name at Naples as understudy to Diego Maradona and won the Uefa Cup with Parma in 1995. In 1996 he joined Chelsea, where fans came to adore him during a seven-year stint.
Team-mates frequently commented on the Sicilian's dedicated approach to training and personal fitness, even in the final years of his career when he enjoyed most of his success.
But while adored in west London and admired throughout the game, Zola, who will celebrate his 39th birthday next Tuesday, won only 35 international caps for Italy and made just six appearances for the Azzurri during his time at Chelsea.Reuse content