Abstract: The surrogate model based on the Kriging model is applied to predict resonant frequency and corresponding sound power level of underwater structural vibration and acoustic radiation.The principal component decomposition is combined with the Kriging model to construct a surrogate model for predicting vibro-acoustic response in the frequency band of interest.These surrogate models give the vibro-acoustic response results in the whole design space in real time based on sample information.An underwater stiffened plate is involved to show the building and verification of the surrogate models.The results show that the Kriging model predicts the resonant frequency and corresponding sound power level with high accuracy.The surrogate model based on the principal component decomposition and the Kriging model gives good approximation of the sound power level in the whole frequency band except at the resonant frequency. The surrogate models can be properly used for design optimization of underwater structural vibration and acoustic radiation.