The invention discloses a splicing and pressing device for a piezoelectric crystal plate of an ultrasonic transducer. The splicing and pressing device is used for splicing the piezoelectric crystal plate onto a housing of an ultrasonic probe or a wedge block of the housing; the pressing device comprises a bottom plate, an upper plate mounted on the bottom plate, and a longitudinal pressing part which is mounted on the upper plate and is used for pressing the piezoelectric crystal plate onto the housing or the wedge block from above; and the pressing device further comprises a transverse pressing part for fixing the wedge block from the side and being capable of regulating the angle of the wedge block. The splicing and pressing device is provided with an angle regulating device, is suitable for splicing wedge blocks of different angles to the crystal plate, enables the spliced plane of the crystal plate to be perpendicular to a pressure rod all the time, ensures stress of the crystal plate to be balanced, is wide in scope of application and is good in universality; an air cylinder drives a guide rod pressing structure, and pressing force is regulated by regulating gas pressure of the air cylinder, so that pressure can be kept constant, and the crystal plate splicing process is guaranteed to be consistent. Glue gas bubbles between the piezoelectric crystal plate and the wedge block can be eliminated, secondary de-foaming is not needed, sound transmission properties of the ultrasonic transducer are improved, and detection flexibility is improved.