The railroad noise has been considered as one of environment pollution and complaints about it have been increasing every year. Therefore, the establishment of railroad noise monitoring network is necessary. It will be designed for monitoring railroad noise, storing data of railroad noise continuously and providing the fundamental knowledge for the measures of railroad noise. For this, we investigated the actual condition and status of railroad noise according to distance around Daejeon, Daegu, Gwangju, and Busan. This paper shows the basic data that will be used for predicting the noise level near railroad in the environmental impact assessment.