Infrared image analytic method is put forth aiming at the thermal distribution of solution and its mutative characteristic in the processing of semiconductor wet etching. As heat is generated and heat convection simultaneously takes place in etching solution during the processing of wet etching, the thermal characteristic could be analyzed effectively with the distribution of infrared image. Experiment results show as follows: in the processing of semiconductor etching, chemical heat centers in the semiconductor material, and is convected gradiently in all directions; the vertical heat convection velocity is obviously swifter than the horizontal; the process of heat convection can be realtimely recorded, and the heat convection situation can be gotten in any small area at any time by infrared camera which makes the analyse and understanding of heat convection characteristic in the processing of wet etching more intuitionistic. This method is valued in precisely controlling the temperature and improving the etching performance in the processing of semiconductor etching.