With the development of the national economy and the automotive industry, urban road traffic has been developing rapidly. At the same time, traffic noise is more serious and has become one of the major noise sources in urban area. Areas along the roads are affected seriously by noise, for example: residential area, schools, hospitals etc.. So the measures should be taken to control urban road traffic noise imminently and quiet environment should be created by raising consciousness about environmental protection of the whole nation gradually. At present one of the main measures is construction of sound barriers. In the paper the inverted L sound barrier model was tested in the hemi-anechoic chamber using the noise and vibration analysis system. Noise reduction effects become gradually less by the less distance between the barrier and the measurement point or by the more height of the measurement point to the ground surface. Noise reduction effect is more in inclination 30°, and noise reduction effect is less in inclination 90°. The conclusions are really worthwhile in sound barrier design.