An ultrasonic testing apparatus for a pipe end portion, which enables accurate ultrasonic testing, comprises an ultrasonic probe disposed under the pipe end portion. The probe 1 transmits ultrasonic waves to the pipe end portion and receives the ultrasonic waves therefrom. A probe holder houses the probe which is disposed under the pipe end portion to face the pipe end portion and follows the pipe rotation. The probe holder comprises a coupling medium reserver part that surrounds a space between the probe and the pipe end portion to contain a coupling medium therein and comprises a coupling medium reserver part body into which the coupling medium is supplied. An annular bellows part, which communicates with the reserver part body, can expand and contract vertically and an annular spacer, which is attached to the upper side of the bellows part and an upper surface thereof has a flat horizontal surface.