Timok (Cyrillic: Тимок, Romanian: Timoc) is a river in eastern Serbia and western Bulgaria.

Timok may also refer to:

• Timok Valley, a region in Serbia around the river
• FK Timok Zaječar, Serbian football club

Tributaries of Timok river:

• Beli Timok
• Trgoviški Timok
• Svrljiški Timok
• Crni Timok