A two-dimensional array ultrasonic probe is provided with a two-dimensional ultrasonic array and a surface protection layer provided on the array. The two-dimensional ultrasonic array arranges a plurality of piezoelectric vibration elements two-dimensionally. The surface protection layer is made essentially of polybutadiene series rubber. The polybutadiene series rubber is synthesized from 100 parts by weight of polybutadiene and 1 to 5 parts by weight of glycerin.
