The results of caspase activation suggested the involvement of caspase-3, caspase-9, and caspase-8 in apoptosis induction, and the considerable reduction of the cytotoxicity of phenethyl isothiocyanate in the presence of the caspase inhibitor confirmed the caspase-3 participation in execution of the apoptosis in phenethyl isothiocyanate–administered cervical cancer cells. Here, CASP9 is linked to cervical cancer.