The present invention provides a leakage detector enabling accurate and stable detection for occurrence and a position of leakage in a buried fluid pipe line and also making it possible for even those not so skilled in the leakage detection work to use the detector. The leakage detector 1 according to the present invention comprises a vibration detector 2 having a pickup 6 incorporating a piezoelectric element; a main body 4 of the detector incorporating voltage amplifiers 31, 37 for voltage-amplifying an output signal and a plurality types of noise removing units 33, 34, 35 for removing noises from the output signal, and a headphone 5. The main body 4 of the detector has a display unit 15 for displaying data for detected vibration sounds on a predefined screen.