Teacher performance evaluation plays a key role in educational personnel reform, so it has been an important yet difficult issue in educational reform. Previous evaluations on teachers failed to make strict distinction among the three dominant types of evaluation, namely, capability, achievement, and effectiveness. Moreover, teacher performance evaluation was usually restricted to task performance, neglecting contextual performance. Most researches done in teachers' evaluation were only about college teachers. This paper suggests that teacher performance evaluation should find its theoretical foundation in teacher performance constructs. After making literature review, critical case study, critical interview, and qualitative research, the authors propose a new construct of teacher performance and make necessary analysis for the construct of reliability and validity in empirical approaches.