Many work-related risk factors can cause construction site hazards. As well, risk for the same trade can vary due to different combinations of inherently changeable construction site characteristics. However, construction safety management has been executed similarly to other industries without reflecting the unique characteristics of the construction industry. To address these issues, this paper proposes a risk assessment methodology that considers the risk influence factors of construction sites and the risk of trade. Through a literature review and expert surveys, this study extracts risk influence factors and develops a weighting system for their classification. Risk of trade is calculated based on frequency and severity of risk. By integrating risk influence factors and risk of trade, this methodology can determine risk according to specific construction site conditions, thus enabling more effective safety management.