From 1988 till 1991 Roberto played for Schaffhausen, the local football club, as a defender. Later, Di Matteo was bought by Zürich, the most titled Swiss club. In 1992, he joined Aarau. He signed for Lazio in the summer of 1993 on a free transfer. Di Matteo became a regular starting-11 member of the Lazio side in midfield under managers Dino Zoff and later Zden?k Zeman.

Di Matteo made his Italy debut under Arrigo Sacchi on 16 November 1994 in the Stadio La Favorita in Palermo. He came on as a 55th-minute substitute for Demetrio Albertini as Italy lost 2–1 to Croatia in qualification for UEFA Euro 1996. He made his first start in his second cap, a friendly 3–1 victory over Turkey on 21 December 1994 in the Stadio Adriatico in Pescara. Di Matteo played two of Italy's group matches in UEFA Euro 1996, against Russia and Germany.

Di Matteo only scored one more goal for Italy, in a friendly win over Slovakia on 28 January 1998. He was a member of Italy's FIFA World Cup team in 1998 and played two of their group games, against Chile and Cameroon. The match against Cameroon in Montpellier was his last game for Italy; in total, he made 34 caps for Italy between 1994 and 1998, scoring 2 goals. At the beginning of 2000/2001 season Di Matteo was seriously injured and had to cease his career of a professional footballer.

In 2002 Roberto was selected in a Chelsea greatest-ever XI. The playing career of Chelsea midfielder Roberto Di Matteo was curtailed prematurely by injury in 2002 and, while running restaurant businesses on the side, he pursued coaching qualifications alongside fellow 1997 FA Cup final-winning goal scorer. In 2008, Di Matteo was appointed Milton Keynes Dons club manager. In 2009, he becomes the head coach of West Bromwich Albion. On 29 June 2011, Roberto was appointed assistant manager to André Villas Boas, the new Chelsea head coach. After Villas stepped down in March 2012, Di Matteo became the Interim leader of the Blues till the end of the season. Under his guidance, Chelsea won the FA Cup and the UEFA Champions League.

On 11 June 2012, Roberto Di Matteo got rid of the ‘Interim’ prefix and was appointed the club manager. In November 2012, Roberto was sacked harshly after a brief run of unsatisfactory results. Chelsea is still paying Roberto Di Matteo a salary of £130,000-a-week. His net worth is about £6.76 million. As to the personal life in his biography, Roberto is married to Zoe di Matteo. According to the wiki, he and his wife have three children and currently live in Leamington Spa, Warwickshire.