Abstract: In the practical application of concrete ultrasonic testing, restricted by the external environmental conditions, the arrangement of ultrasonic transducers generally has two ways, and the corresponding detection methods are divided into ultrasonic opposite testing method and ultrasonic level testing method. In order to compare the accuracy of these two commonly used concrete ultrasonic testing methods, it is necessary to test them. By conducting comparative experiments on different distances, sides and bottoms, and comparison tests using ultrasonic level testing method, and analyzing and comparing the regression curves of concrete ultrasonic velocity obtained under different testing conditions, the experimental results showed that the ultrasonic level testing method can replace ultrasonic opposite testing method in detecting concrete strength.