The present invention provides an antistatic agent of the formula (I) R--SO.sub.3NR'R''R'''R'''' (I) wherein R represents a perfluorinated cyclic or linear, branched or unbranched carbon chain having 1 to 30 carbon atoms, R' represents a cyclic or linear, branched or unbranched carbon chain having 1 to 30 carbon atoms, which is unsubstituted or substituted with halogen, hydroxy, cycloalkyl or alkyl, and R'', R''', R'''' independently represent a cyclic or linear, branched or unbranched carbon chain having 1 to 30 carbon atoms, which is unsubstituted or substituted with halogen, hydroxy, cycloalkyl or alkyl, with the proviso that at least one of the radicals R', R'', R''' and R'''' must not represent ethyl. The antistatic agent of the present invention may be incorporated in plastic molding materials to provide antistatic properties thereto.