The need to understand how to implement the structural quieting into the design processes has led the engineers to pay more attention to noise generation and transmission from the vibrating structures. In this study, utilizing the finite element software ABAQUS, the acoustical and vibrational response of stiffened steel plate opening wall in a RC room subject to blast has been investigated. Moreover, frequency analysis has been performed on each of the stiffener arrangements, in order to obtain the transmission loss of the generated noise in frequency domain under the effect of a diffused field of a white noise. The three stiffener arrangements of diagonal, cross, and parallel have been used in the analysis. The results indicate that the stiffener arrangements has marginal effect on the vibrational response of the system, whereas its influence on the acoustical response of the system is substantially high. For instance, the cross and diagonal stiffeners showed, in a descending order, the best performance in the noise transmission loss of the system.