This main purpose of this study was to investigate the effects of curriculum-based assessment on promoting resource-room students’ performance and decreasing their anxiety in mathermatical problem solving. The subjects in this study were 4 resource-room students of Yong-Ho elementary school in Taipei County. Four students were treated by curriculum-based assessment for two months. The results were summarized as follows: 1. The CBA could promoting subjects’ mathermatical problem solving performance. 2. The CBA could effectively decrease students’ anxiety in mathematics. Based on the results of this study, the effects of curriculum-based assessment on resource-room students’ performance and anxiety of mathermatical problem solving were explored, and implications for teaching and further research were addressed.