Abstract: Ultrasonic phased array equipment is used to detect the propagation wave speed of ultrasonic waves in concrete, and the correlation between wave speed and concrete configuration strength and age is investigated. First, multiple groups of concrete specimens with configuration strengths of C30\C40\C50 were formed, and ultrasonic phased array line scanning tests were conducted at 4 days, 15 days, and 30 days respectively. By reading the peak delay time of each ultrasonic signal during the test, the propagation wave speed of ultrasonic waves in concrete can be inferred. The test results show that: the test results of ultrasonic wave speed on the same specimen have good repeatability, revealing that the dry contact ultrasonic probe has good working performance; when the ultrasonic frequency changes within 20-60 kHz, the change in concrete ultrasonic wave speed is less than 1%; no There are significant differences in the wave speed of concrete at the same age and with different configuration strengths, showing that the ultrasonic phased array wave speed can distinguish the strength characteristics of concrete. A concrete wave velocity test was conducted on the surface of a certain prefabricated component on site, and the low wave velocity areas found were verified to contain concrete quality defects.