Abstract: The first-order and second-order statistical properties of ultrasonic speckles reflected from a rough interface were studied theoretically and experimentally. Under the condition of three assumptions the theoretical analyzing results show that the amplitude and the phase of the ultrasonic speckles are Rayleigh and uniform distributed respectively, and the average transverse size of the speckles which are measured by a focus probe in the scattering space is only dependent on the characteristics of the experimental system and independent of their positions in the space. In order to verify the theoretical analyzing results, experiment is performed in a specific experimental setup. The sound pressure of the ultrasonic speckles reflected from a rough interface between water and Aluminum alloy were measured by a circular focus probe. The experimental results show that the assumptions are reasonable and the theoretical analyses are correct.