本研究目的在探討能力信念、學業自我價值後效與學業成就對國小學生學習動機與學習情緒之影響。研究中採2 × 2 × 2準實驗三因子設計（能力信念 × 學業自我價值後效 × 成就)，對象為台北與高雄各一個國小的六年級學生，共四個班級121名，其中兩班在「能力增長觀」之信念下學習「科學文章」，兩班則在「能力實存觀」之信念下學習。另外，並依據四班學生在「學業自我價值後效量表」以及「成就測驗」上之得分，將學生區分為高、低學業自我價值後效與高、低成就組。實驗結束後，分別以國小科學知識學習動機量表、國小科學知識學習情緒量表前測為共變項，能力信念、學業自我價值後效和成就為自變項，後測為依變項，進行三因子多變量共變數分析。分析結果顯示：（一）在「能力實存觀」、「高自我價值後效」的情況中，高成就學生在價值、預期與情感等向度之學習動機皆高於低成就學生，然而在其他情況則未有差異。（二）「增長觀」組較「實存觀」組感受到較高程度的緊張情緒。本研究根據研究目的、結果與相關文獻進行討論，並提出結果應用及未來研究的建議。

The purpose of this study was to examine the effects of ability beliefs, academic contingencies self-worth (ACSW), and academic achievement on elementary school students’ learning motivation and affects. A three-factor quasi-experimental design (2 × 2 × 2) was adopted. Participants were 121 sixth-grade students of four intact classes from two elementary schools in Taipei and Kaohsiung. Students of two classes were primed with the incremental ability belief when learning science article, and the others primed with entity ability belief. Furthermore, the students were divided into high and low ACSW groups by their scores on ACSW Scale and high and low achievement groups by their scores on The Science Article Achievement Test. Data were analyzed using a three-way ANCOVA. The independent variables were ability beliefs, ACSW, and achievement. The covariates and dependent variables were pretest and posttest scores, respectively, of Elementary School Science Knowledge Learning Motivation Scale and Elementary School Science Knowledge Learning Affect Scale. Results Suggested that students with high achievement showed higher learning motivation on value, expectation, and affect components than low achievement students only when they had high ACSW and were primed with entity ability belief. There were no differences under other circumstances. Also, students who were primed with incremental ability belief experienced higher nervous affect than students primed with entity ability belief. Finally, based on the research findings, implications for educators and suggestions for future research were provided.