The present invention relates to an ultrasonic generator for repelling harmful animals. The present invention comprises: a cylindrical ultrasonic generator body (18) comprising a piezoelectric device (16) and having a connection body (22) with a decreased diameter and a small-diameter connection body (24) a speaker horn-shaped vibrational plate (28) and a connection rod (26) extended from the ultrasonic generation body (18) such that the vibrational plate (28) is connected and fixed to the end part thereof, wherein the thickness of the vibrational plate (28) gradually decreases toward the outer side part from a base part (34) to be fixed to the connection rod (26), and several bent parts (36) are concentrically formed on the front surface of the vibrational plate (28).
