Abstract: Concrete uniformity testing is one of the key technologies in concrete construction quality control. Based on ultrasonic technology, uniformity testing experiments were conducted on fresh concrete at different mixing times to obtain the density of concrete at different points and calculate the uniformity index of concrete at different mixing times. The experimental results showed that the reasonable mixing time for fresh concrete using a single horizontal axis mixer was 100-150 seconds. By analyzing the degree of conformity between the regression curves of three fitting functions and the measured relationship curves, a specialized measurement uniformity curve fitting function with a higher degree of conformity was determined. According to this, it can be seen that ultrasonic technology can effectively detect concrete uniformity and to some extent guide the on-site construction of fresh concrete.