| Club: | Beşiktaş J.K. |
| Stadium: | İnönü Stadium |
| League: | Süper Lig |
| Season: | 2002–03 |
| League Result: | 1st |
| Cup1: | Turkish Cup |
| Cup1 Result: | Quarterfinals (eliminated) |
| Cup2: | UEFA Cup |
| League Topscorer: | |
| Season Topscorer: | |
| Chrtitle: | President |
| Chairman: |  Serdar Bilgili |
| Manager: | Mircea Lucescu |
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| Prevseason: | 2001–02 |
| Nextseason: | 2003–04 |
The 2002–03 season was the club's 44th season in the Turkish Super League and the club's 100th year in existence. After signing Romanian manager Mircea Lucescu, Beşiktaş won the league for the 12th time in club' history. Beşiktaş also had their most successful UEFA Cup run, by becoming a quarter finalist, however the club lost to S.S. Lazio 1–3 on aggregate, therefore eliminating them. Beşiktaş lost to Gençlerbirliği 3–4 in the quarterfinals of the Turkish Cup.
Source:[1]
See main article: 2002–03 Süper Lig.
See main article: 2002–03 Turkish Cup. Beşiktaş had a bye in the first round and then played Elazığspor in the second round. Beşiktaş lost to Gençlerbirliği in the quarter finals.
Beşiktaş had their most successful run, by becoming a quarter finalist. In doing so, they became the second Turkish team to achieve the feat (Galatasaray achieved it in 2000).
Beşiktaş won 7–2 on aggregate.
Beşiktaş won 2–1 on aggregate.
Beşiktaş won 3–1 on aggregate.
Beşiktaş won 4–3 on aggregate.
Beşiktaş lost 1–3 on aggregate.