Community noise, especially a rail traffic noise has been serious social issues in Korea. Our society needs practical tools to reduce noise levels for public who live near the railway lines. This paper proposes a noise reducer for railway traffic noise. At the beginning, various types of reducers are discussed, with the advantages and disadvantages with respect to acoustical phenomena. Then, the acoustic effects are discussed based on an insertion loss measurement. After several types of reduces are installed at fields, the noise level is monitored with and without the reducer. The result shows that the proper selection of reducers affects the noise level by 6 dB. The statistics of the mean and a standard deviation turns out to be 3.2 dB and 0.8 dB, respectively. Noise reducers are strongly recommended for the place where apartments are densely constructed alone the railway. Installation of noise reducers seems to be an effective and practical solution for the community traffic noise reduction.