The demand for glass cutting quality in various fields becomes higher nowadays. As an emerging cutting, laser induced thermal fracture cutting has great advantages over conventional cutting methods. However, the crack propagation trajectory deviates from the desirable path during the cutting process. To eliminate this phenomenon, compensation strategy is needed via the in-situ monitoring on crack propagation state. As a sort of non-destructive testing methods, acoustic emission(AE) has excellent potential on it. In this paper, modal analysis and wavelet packet analysis were carried out for the acoustic emission signal released during Acoustic emission occurs during laser induced thermal cracking of the glass,s. In this paper, modal analysis and wavelet packet analysis were carried out for this acoustic emission signal, and the basis of optimal wavelet basis and decomposition scale selection is determined. In the experiment, the position of the crack tip was analyzed by optimizing the layout of the sensor and using the time difference positioning method. On this basis, the experimental study on laser induced thermal cracking glass acoustic emission signal monitoring was carried out, and the relationship between AE signal characteristics and crack propagation state was explored.