To measure the critical pressure when intense cavitation occurred in liquid, a method to detect the critical intense cavitation pressure which based on the acousto-optical refraction effect is proposed. According to the distribution of the far-field spot which changes with time to determine the occurrence of intense cavitation, it can detect the value of the critical intense cavitation pressure non-invasively by the relation between the maximum deflection distance of the ray and the change of the focus acoustic pressure with a high repeatability. By analysing the distribution of the cavitation bubbles in liquid , and the cavitation threshold pressure changing with the external environmental pressure to calibrate the results, it′s proved that the feasibility of this way to detect the critical intense cavitation pressure.