我國自一九九五年正式全面施行環境影響評估制度，該制度的特度為調查、審議程序之公開，其核心則為「利害關係人」(stakeholder)之參與。然而觀察國內環評案例，發現民眾對現有環境影響評估公開的程序、民眾參與的管道等不了解與不信任而參與低。本文透過對環境影響評估個案中參與機關與民眾代表進行深度訪談，同時以Icek Ajzen「計畫行為理論」(The Theory of Planned Behavior)為架構，建構一「臺灣民眾參與環境影響評估行為意圖」探索性模式，針對286位的民眾進行問卷調查，並採用「結構方程式模型」(Structural Equation Modeling)方法分析此意圖模式，依據資料結果對環評制度中民眾參與機制提出建議。 Despite the fact that there has been an official design of citizen participation in Taiwanese Environmental Impact Assessment (EIA) system since 1995, the design remains unpopular and untrustworthy in our society due to problems such as inefficiency, political complexity, etc. In this paper, we examine the antecedents of the EIA citizen participation behavior in the context of an integrated behavioral mode. This model incorporates our previous depth interview and a wide variety of important factors from previous research on environmental behavior into a single theoretical framework provided by the Theory of planned Behavior. The model was tested using data from a sample of 286 individual respondents, each of whom completed a survey. The results suggest that this model fits the data fairly and provides certain insight into the factors that influence citizen participation in environmental impact assessment. We draw public policy implications and focus on a more open and more effective process for operating citizen participation based on the results.