Abstract: This paper describes a theoretical model to predict the vibrating behaviour and the near-field scattering performance of one fmite plate inserted in a rigid cylindrical baffler, while the plate is made of the composite material which contains three reinforced thin layers. Interaction between normal modes owing to sound-medium coupling is taken into consideration. In the mean-while,the self-coupling and mutual-coupling coefficients of various' modes of vibration are calculated numerically. And then, amplitudes for every mode of the composite plate and values for the near-field scattering of the vibrating system are calculated also. We have proceeded to measure the characteristics of the near field scattering about the vibration system. Experimental results are comparatively consistent with theoretical values.