An electrophotographic toner composition, improved in uniform dispersion therein of carbon black and electrophotographic properties, comprises a binder polymer, carbon black and a compound selected from the group consisting of a sulfonate compound having the formula (I), an alkaline earth metal salt of a basic alkylphenol persulfide having the formula (II), an alkyl or alkenyl succinic acid imide having the formula (III-1) or (III-2), an alkyl salicylic acid salt having the formula (IV), a compound having the formula (V) and a product obtained by treating the compound (V) with sulfur, in which R, R', R1 and R2 are a substituent and M is an alkaline earth metal. ##STR1##