近年來，正向心理議題的研究（如心理資本、情緒幸福感）逐漸受到重視。本研究旨在探討大學生心理資本與憂鬱的關係，以及情緒幸福感能否扮演心理資本與憂鬱傾向之間的中介角色。研究以全國1216名大學生為對象，研究工具採用「心理資本量表」、「情緒幸福感量表」與「臺灣憂鬱情緒量表」做為研究工具，透過實徵資料的蒐集，利用描述統計、結構方程式模型進行分析。研究結果發現：（1）大學生的心理資本對情緒幸福感之直接效果達到顯著，而情緒幸福感對憂鬱的效果亦達到顯著。（2）情緒幸福感在心理資本與憂鬱之間扮演完全中介變項的角色。最後，根據研究結果，針對高等教育現場與未來研究方向提出各項建議。 Nowadays, research in the field of positive psychology issues (e.g., psychological capital, emotional well-being) is becoming increasingly significant. The main purpose of this study was to investigate the relationships between psychological capital, emotional well-being, and depression of college students. This study adopts a survey research method which comprised of three questionnaires such as: “Psychological Capital Scale,” “Emotional Well-Being Scale,” and “Taiwan Depression Scale.” Participants were 1,216 college students randomly selected from colleges and universities in Taiwan. The collected data were analyzed by descriptive statistics and structural equation modeling. And the findings are summarized as follows: (1) Psychological capital could significantly and positively predict emotional well-being, and the emotional well-being could significantly and negatively predict for depression, too. (2) Emotional well-being plays the full mediator role for the prediction from psychological capital to depression. Based on the results, discussion and suggestions for higher education practice and future research were proposed.