This research adopts 532-nm and 1064-nm laser sources to study laser-induced cavitation bubbles and their time evolution and the spectra of laser-induced plasma emission in bulk water, respectively. The effects of laser wavelength and focus position of the focusing lens on cavitation bubbles and spectral intensity are discussed in detail. The results show that under the same experimental parameters, laser-induced cavitation bubbles have two periods of expansion-contraction oscillation in both cases. Nevertheless, cavitation bubbles produced by the 1064-nm laser have larger diameters and higher expansion speeds, and their intensity of laser-induced breakdown spectroscopy (LIBS) reaches 2.3 times that in the case of the 532-nm laser. Spectral intensity, cavitation bubble size, and their stability are closely related to the focus position of the focusing lens. A focus 10-12 mm below the water surface can not only produce cavitation bubbles with larger diameters and favorable stability, but also reduce the relative standard deviation of the spectral line intensity of LIBS from 20% to 13% and thereby improve the stability of the intensity.