Dynamic characteristics of cavitation bubbles and hard tissue ablation induced by fiber-guided free-running holmium laser pulses are recorded by high-speed photography. At the same time, a needle hydrophone is used to measure shock wave signals which are emitted upon cavitation bubble collapse. Experimental results show that more than four oscillation periods of 368, 144, 56 and 40 μs, respectively, are achieved. During the oscillation process, most energy focuses on the first period and the cavitation bubble becomes more and more irregular in shape. The intensity of the four shock waves reaches 20.5×105, 12.6×105, 5.1×105 and 2.0×105 Pa, as cavitation bubble collapse, respectively. The water layer on hard tissue surface can not only enhance ablation efficiency, but also improve lubricity of ablation craters.