Tajik may refer to:

• Tajiks, an ethnicity with dwellers in Tajikistan, Uzbekistan, Afghanistan, and China
• The Tajik language, the official language of Tajikistan
• Tajik, one of the of the 56 nationalities officially recognized by the People's Republic of China.

note: inhabitants of Tajikistan, and the related adjective are Tajikistani(s)