By using the methods based on pulseecho method, A-scan method, longitudinal wave method, single probe method and immersion method, the longitudinal sound velocities of aluminum and copper chip substrate were measured. The two methods of changing the sound path based on transducer movement and based on reflecting undersurface change were respectively used to calibrate the sound velocity in water, and the measurement error of the system was 0.13%. Adopting the method of changing the sound path based on reflection interface change, the sound velocities of aluminum substrate and copper substrate were measured. Within the 90% confidence probability interval, the sound velocity of aluminum and copper substrate are (6 375.97±29.97)m/s and (4 655.70±28.24)m/s respectively. The simulation results are similar to the measurement results, which shows that the measurement method has high accuracy. The measured sound velocity can be used to study other physical characteristics of the chip as well as the bonding quality of the connection and internal interface of the chips.