PURPOSE: To produce the title surfactant having high surface tension lowering power even at low concn. by forming an amido cpd. through the reaction of a specific polyfloroalkylcarbonyl cpd. and a piperazine derivative and reacting the amide cpd. with a carboxylating agent.

CONSTITUTION: A polyfluoroalkylcarbonyl cpd. of formula I (where Rf is 1W20 C polyfluoroalkyl, Z is -OR, X or -OC(=0)Rf, R is H or lower alkyl, and X is a halogne atom) is reacted with a piperazine derivative of formula II (where A is alkyl or hydroxyalkyl) to form an amido cpd. of formula III. This amido cpd. is then reacted with a carboxylating agent such as monochloroacetic acid to produce a novel surfactant of formula IV (where B is 1W5 C divalent alkylene) by amphoteric reaction in which carboxylation and quaternization are simultaneously carried out.