The purpose of this study was to evaluate the perceived distance from home to high-voltage power lines using a transmission and substation geographic information system(TGIS). Of the 725, 136 respondents reported that high voltage power transmission tower, power lines or substation was within visual field range from home. Among them, 114 respondents reported valid address, which could be used in the analysis of TGIS. Forty two respondents(36.8 %) estimated that the power lines were closer and 15 respondents(13.2 %) estimated that they were farther than they actually were. Our current findings suggest that the reported distance from home to high-voltage power transmission towers, power lines, and substations cannot be used as a proxy for exposure to electromagnetic fields due to the low validity.