本研究旨在了解不同性別國小學生的數學內、外在動機及要素之間是否有差異，高低內、外在動機者的數學學業表現是否有差異，並探討最能預測國小學生數學學業表現的動機層面及其要素。本研究使用文獻探討和問卷調查法，主要結果有三：首先，男生的數學內在動機高於女生，外在動機則無性別差異；其次，「高內在動機者」的數學學業表現高於「低內在動機者」，且其要素皆有差異存在，而「高外在動機者」與「低外在動機者」的數學學業表現並無差異，但「高達成有用價值者」、「高相對能力目標導向者」的學業表現卻分別高於「低達成有用價值者」、「低相對能力目標導向者」；第三，「內在動機」對數學學業表現的預測力大於「外在動機」，且內在動機的能力自我概念對數學學業表現有較大的預測力，外在動機的相對能力目標導向對數學學業表現有較大的預測力。本研究根據研究結果提出具體建議作為未來相關研究之參考。

The purposes of this paper were: (1) to realize the differences of intrinsic, extrinsic and the elements between male and female students; (2) to explore intrinsic and extrinsic motivation in predicting mathematical performance for primary school students. The results were as follows: Firstly, male students had higher level of intrinsic motivation than female students. The major reason was self-concept of competence of students. There were no gender differences in extrinsic motivation. Secondly, students with higher intrinsic motivation and the elements had higher mathematical performance. There were no performance differences in extrinsic motivation, but students with higher attainment and utility value had higher mathematical performance, students with higher goal orientation of relative competence had higher performance. Thirdly, intrinsic motivation exhibited a more prediction compared with extrinsic motivation. Based on the result of the study, recommendations were made for the other researchers.