Liquid carbon dioxide rock-breaking (L-CDRB) is a new physical blasting technology. To study the characteristics of its vibration velocity, rock-breaking field tests were conducted using a new type of liquid CO2 fracturing tube. Comparisons were made between explosive blasting and L-CDRB in terms of the peak values, frequencies, and energy distributions of the generated vibration velocities. The results show that (1) for the same scaled charge, L-CDRB (vs. explosive blasting) produced a smaller peak, a lower dominant frequency, and simpler frequency components of vibration velocities than explosive blasting. (2) The dominant frequency and energy distribution were related to the total liquid CO2 filling quantity. Higher total filling quantities resulted in higher dominant frequencies, and the energy distribution shifted from a low to a high-frequency band.