Tetrabutyltin is the organotin compound with the molecular formula Sn(CH2CH2CH2CH3)4 or SnBu4, where Bu is butyl −CH2CH2CH2CH3.

Sometimes abbreviated TTBT, it is a colorless, lipophilic oil.

[3] Tetrabutyltin is a precursor to tributyltin and dibutyltin compounds.

By the redistribution reaction with tin(IV) chloride it forms tributyltin chloride and dibutyltin chloride.

These compounds are starting materials for a wide range of organotin compounds used as stabilizers for PVC and as biocides, fungicides, wood preservatives, and (historically) marine anti-biofouling agents.