According to the characteristics that a laser induced bubble is filled with mostly water vapor and a little noncondensable gas, a specific Rayleigh-Plesset equation which was used to determine the position of the dynamic bubble wall and other concerned conditions were used. Mass diffusion between the bubble and the gases dissolved in surrounding water, compression of water, condensation and evaporation at the bubble wall, heat conduction, sound radiation, viscosity of water and surface tension were considered. A laser induced bubble producing, photographing and pressure measuring system was set up. Numerical and experimental method was used; the relative error of pressure inside bubble was under 10%. The relations were showed among the absorbed laser puergy, the pressure and the temperature in the bubble and the bubble radius.