This study was performed to evaluate characteristics of illegally dumped construction wastes in the riversides of Nakdong river. We tried to determine whether these construction wastes contained toxic compounds and stabilized. Wastes were found at 4 sampling points and these wastes were not classified as toxic wastes. Instead, these wastes were classified as construction wastes. In addition, these construction wastes were not contaminated by toxic heavy metals, anions, and organic compounds according to soil pollution guidelines. Thus, these construction wastes can be recycled or treated as construction wastes according to the guideline provided by Korea Ministry of Environment.