Zola signed his first professional contract with Sardinian team Nuorese in 1984. In 1986 he moved to Torres from Sassari, and three years later he signed for Napoli in Serie A. The young and talented Zola scored two goals as understudy to Diego Maradona as Napoli won the Italian title in 1990. Maradona would prove to be a big influence on Zola's career. The two would spend hours practising free kicks together after training and Zola later said that "I learned everything from Diego. I used to spy on him every time he trained and learned how to curl a free-kick just like him." He helped Napoli to win the Italian Super Cup in 1991 and he made his debut for the Italian national side under coach Arrigo Sacchi in the same year. In 1993, Zola left Napoli and joined fellow Serie A side Parma. He won the UEFA Cup with Parma and they were runners-up in Serie A and the Italian Cup in 1995. It was with the blue and yellow club that he cemented his reputation as a creative player. However, coach Carlo Ancelotti came to see Zola as a "square peg" unable to fit into his rigid system. Zola was played out of position and ultimately made available for transfer.

In November 1996, Zola joined English Premier League club Chelsea F.C. for £4.5m as one of several continental players signed by Ruud Gullit. He made an immediate impact in English football, putting in a series of virtuoso performances. He scored with a curling shot from 25 yards against Liverpool in the FA Cup and another against West Ham United following a darting run, during which he wrong-footed defender Julian Dicks several times. After spiriting the ball around Manchester United's defence in the penalty area before slotting the ball past Peter Schmeichel, he was described by United manager Alex Ferguson as a "clever little so-and-so." Zola played a significant part in Chelsea's. resurgence that season as they won the FA Cup. Other than the curling strike in the 4-2 comeback game against Liverpool, probably his best FA Cup goal was the "twisted blood" move in the semi-final against Wimbledon. He was running full speed acros the penalty box when a pass was played into him. In one movement he backheeled it into the space he had just run from and turned 180 degrees to follow it, leaving the defender for dead and smacked it into the bottom corner.

He was voted the English Football Writers' Player of the Year in 1997: the only player ever to receive the accolade without playing an entire season. (He came second in his final season 2002-3, too)

In 1998 he helped Chelsea win the English League Cup, the UEFA Cup Winners' Cup and the Super Cup. An injury denied him a place in the starting line-up for the Cup Winners' Cup final against VfB Stuttgart at the Råsunda Stadium in Stockholm, but he came as a second half substitute, scoring 21 seconds later. Only his second touch of the game, he smashed a through ball from Dennis Wise past goalkeeper Wohlfahrt into the roof of the net to secure Chelsea's third major trophy in a year and the second European trophy in the club's history. He helped Chelsea to win FA Cup again in 2000.

Though never a prolific goalscorer, Zola gained a reputation for scoring outrageous goals at Chelsea. In a Premier League match against Tottenham Hotspur in January 2003, he curled a free kick from 25 yards out high and wide into the top corner at the far post past a hapless Kasey Keller. In an FA Cup tie against Norwich City he received the ball in mid-air from a corner kick and managed to back-heel it into the net. His farewell Chelsea goal came against Everton at Stamford Bridge with an outside-of-the-foot lob from outside the box over Richard Wright.

In early 2003, 'Franco was voted as the best ever Chelsea player by Chelsea's fans. In November 2004, he was awarded an OBE - Honorary Member of the Order of the British Empire in a special ceremony in Rome. In 2005 Zola was voted into the Chelsea FC Centenary Eleven, occupying one of the two "forward" roles.

In the summer of 2003, amid rumours of an impending takeover at Chelsea, Zola left Chelsea FC to join Cagliari, a club from his native Sardinia. Within a week Chelsea FC was purchased by Russian billionaire Roman Abramovich. Unable to persuade Zola to renege on his verbal contract with Cagliari, Abramovich attempted to purchase the entire Cagliari club. His offer for the club was rejected. Zola subsequently led Cagliari to promotion to the Italian Serie A. Then he renewed his contract for Cagliari Calcio for one more year. He retired in June of 2005, after ending his career in appropriate style with a double against Juventus in his last ever professional game. His number 10 jersey was retired by Cagliari, as was his number 25 jersey for Chelsea.

Despite speculation he would play on in the 2005/2006 season, Zola decided to leave the game, just a week before he turned 39. He is currently an Italian football pundit, though he also comments on European competitions. He has also been named joint coach of the Italian Under-21 side with ex Chelsea player Pierluigi Casiraghi.

Zola played for his country at the 1994 FIFA World Cup and Euro 96. He last played in a World Cup qualifier against England in Rome in October 1997. Zola won 35 international caps, scoring 8 goals. His international career is best known to English fans for his goal against England at Wembley, and Chelsea fans were stunned that the Italian team didn't take him to France in 1998.

A true modern-day football genius, Gianfranco paved the way for many other foreigners to join the English game, while still being highly regarded in Italy. He scored 80 goals for Chelsea, including 14 superb free-kicks. No senior Chelsea player has been assigned Zola's jersey number 25 in the four seasons since his departure.

In his entire career, Zola played 627 games and scored 193 goals.

In 2006, Zola started his coaching career, being appointed as assistant to Italy national under-21 football team head coach Pierluigi Casiraghi by the Italian Football Federation. The duo, who were already teammates at Chelsea, led the azzurrini to gain a spot at the 2008 Olympic Games in Beijing, where they reached the quarter-finals before being defeated 3-2 by Belgium. On the 9th September, 2008 Zola agreed a three-year contract to manage West Ham United, replacing Alan Curbishley, who resigned following differences with the board. He was unveiled as new manager on the 11th September.

Napoli
Serie A winner:1989-90

Parma
UEFA Cup winner: 1995

Chelsea
FA Cup winner: 1997, 2000
League Cup winner: 1998
UEFA Cup Winners' Cup winner: 1998

Personal Honours
Awarded an OBE in 2004.

Inducted into the English Football Hall of Fame in 2006 in recognition of his achievements in the English league.

Voted Chelsea's greatest-ever player.

Named in Chelsea's centenary XI.