Trichlorobenzene (TCB) may refer to any of three isomeric chlorinated derivatives of benzene with the molecular formula C₆H₃Cl₃. They differ by the positions of the chlorine atoms around the ring:

• 1,2,3-Trichlorobenzene
• 1,2,4-Trichlorobenzene
• 1,3,5-Trichlorobenzene