The leaf can be seen as shin plate structures with stiffener(vein) and the venation distributions are closed related to the external environment load. Leaf venation growing algorithm (VGA) is the abstract description of vein growing process and reflects an ideological of learning from nature. This article concerns the sound insulation property of thin-walled stiffened plates. Numerical method is used to analyze three types of plants: non-stiffened plate, traditional stiffened plate and VGA stiffened plate. The VGA stiffened plate optimized by leaf venations growth algorithm method can reflect the influence of venations layout structure on the noise reduction performance of forest belts. The computational model of sound transmission through a stiffened plate excited by a harmonic oblique incident plane wave and mounted in an infinite baffle using the coupled finite element/boundary element approach is presented. The proposed model also takes the acoustic fluid- structure coupling into account. The results show that the sound transmission losses are closely dependent on the natural frequency. The sound transmission losses of bionic thin-walled stiffened plate are 0.17-2.45dB more than that of traditional stiffened plate in the range of 900-2000Hz. It indicated that the layout of stiffeners is an influence factor for noise reduction for plate structures, just like that of vein layout for tree belts. There is a certain merit to use the method of bionic plant leaves for acoustic optimization.