Composite materials are frequently used in automobile and other moving vehicle structures. External and internal sounds sometimes cause unpleasant effects on the users and environment, and reduction of such sound is one of the key engineering problems. This study presents an acoustic radiation analysis from forced vibration of laminated rectangular plates and proposes a design approach to reduce the sound pressure from the plates. In the analysis the sound pressure at an arbitrary point over the plate is derived and is used as an object function in the optimization. A set of the fiber orientation angles is used as the design variable, and is optimized to minimize the sound pressure at the designated point. It is shown in numerical examples that the optimum design for sound pressure reduction is possible by the present approach.