本研究旨在探討教師透過數學教學案例討論對教師教學問題解決能力之影響。於國小進行個案研究，蒐集討論前後訪談、教學案例討論的錄影錄音、省思扎記等質性資料進行內容分析。研究結果如下：教學案例討論，提升教師教學問題的界定能力；以問題為核心的教學案例討論模式，有助於提升教師的問題解決能力；在案例討論過程時，分段呈現教學問題解決歷程，有助於教師主動建構專業知識；掌握核心概念的主題式教學案例討論，能促進系統化教學專業能力。研究建議，核心主題教學案例待有系統的建構。其次，案例撰寫不宜過長，以免影響討論品質。最後，參與教師講述式的教學習慣，是否改變為引導式教學，宜進一步做個案研究，了解改變因素。

This study aimed to explore in-service mathematical teachers' problem-solving ability through the discussion of teaching cases. The study was conducted in an elementary school and the data were collected from the interviews before and after the teaching cases, video recordings of the discussion, and the reflective journals were analyzed. The findings are as follows: the discussion of teaching cases enhanced the teachers' ability to define the teaching problems; the discussion model of problem-based teaching cases strengthened the teachers' problem solving ability; the process of segmented case discussion with focused teaching problems helped teachers to actively construct their professional knowledge; and the theme-based teaching cases enabled teachers to grasp the core concepts of each case and reinforced their professional competence of systematic teaching. The study suggested that the core themes of teaching cases be systematically constructed. Secondly, long written case studies should be avoided, so the quality of discussion is not affected. Finally, the expository teaching habits of some participant teachers could change into guided teaching mode so the further case studies are investigated to verify the underlying factors.