To meet the demand of high temperature ultrasonic detection technology in morden society, one type of high temperature piezoelectric ultrasonic transducer with 1 MHz is designed and manufactured in this paper. The high temperature piezoelectric ceramic material BS-PT is used. The PiezoCAD software is applied to simulate the high temperature transducer. The electrical and acoustic properties of this ultrasonic transducer are investigated at room temperature and 200 ℃ in detail. The results show that the echo amplitude decreases slightly with the increase of test temperature. The center frequency and bandwidth of the transducer also change slightly, and the bandwidth remains at about 20%. All the results demonstrate that the high temperature piezoelectric ultrasonic transducer based BS-PT can operate at 200 ℃ stably.