Abstract: The structure of sandwich panels bonded by brazing and transient liquid diffusion welding was analyzed from mechanical properties and vibration damping. Structure optimization of the sandwich panels was performed with the thicknesses of plate and honeycomb, and the length and thickness of honeycomb sides as the designed variables, and with shearing strength, bending strength, bending rigidity, critical bucking load, inherent frequency and mass as the objective functions. The optimized data were studied by test. Experimental results showed that the mechanical properties and vibration damping of the optimized sandwich panel were better than those of the compared sandwich panels, and the tested values were basic coincident with the calculated ones. This structure design can be used for vibration damping sandwich panels and commercial production.