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This research focuses on measuring the mode transformation and energy attenuation of wedge waves by the laser ultrasound technique.First,the finite-element method was used to simulate the laser-induced wedge waves and different orders of wedge-wave modes with nondispersion could be clearly observed.Then the pulsed laser excitation and optical deflection beam method for detection was developed to investigate the wedge waves experimentally.Plenty of wedge waves at different locations were recorded by scanning the excitation laser along the wedge tip,and different orders of wedge waves were observed.By fixing the distance between the excitation and detection position and scanning the samples along the direction normal to the wedge tip,the mode transformation process was achieved.Finally,it was found that the energy of acoustic waves decreases exponentially to a steady energy of the Rayleigh wave within the main wavelength range of these modes.