The present invention provides an animal ectoparasite-controlling agent and a method for preventing or treating infection in animals caused by parasites by using the controlling agent. An animal ectoparasite-controlling agent exhibiting excellent insecticidal activity, and a method for preventing or treating infection in animals caused by parasites by using the controlling agent are obtained by using a compound having a pyrazole ring at the 4-position of the piperidine ring as an active ingredient.
