A theoretical model was developed to evaluate the reduction of structure-borne noise that is generated by a line force applied on an infinite plate using an air-voided elastomeric baffle. The vibrating plate is covered with an elastomeric baffle layer to reduce the noise generated by the structural vibration. The vibrating plate is perfectly bonded to the elastomeric baffle layer. The outer surfaces of the vibrating plate and the elastomeric baffle are in contact with air and water, respectively. The analysis for modeling is based on the theory of elasticity and pertinent boundary conditions. Effects of various parameters such as baffle layer dimensions and material properties on the noise reduction are presented.