Abstract: The study aimed to identify the effectiveness of the Teacher Performance Evaluation System of government primary schools' teachers in the Kingdom of Bahrain, from their own perspective; in terms of teaching performance quality, professional development, and the mechanism of implementing the system by evaluators. It also aims to explore differences between the teachers' estimations due to the variables of experience educational and school assessment by Education and Training Quality Authority. As well as, to identify the challenges facing the implementation of the Teacher Performance Evaluation System (TPES), and suggestions that could develop its application based on teachers point of view. The sample of the study consisted of (638) male and female teachers, (20.6%) of the study population. The researcher relied on the descriptive and comparative method, in which the main instrument used was a questionnaire that included closed questions represented in (36) sentences dropped in three dimensions. First: the quality of teaching performance, second: Professional development and the third: system implementation mechanism by evaluators, in addition, two closed questions addressed the challenges of proposals related to TPES. The researcher enhanced interviews with a number of teachers. This study has reached a set of results including: the lack of difference between the averages of responses and the point of neutrality for each of the three dimensions, since the average responses raised from neutral point statistically. This indicates that the implementation of the teacher evaluation system contributes to raising the quality of the teaching performance, professional development, and shows that those who supervise the system are committed to mechanisms implementation. It also specifies that there were no statistically significant differences in teachers' estimations for the three dimensions, due to teaching experience variable, and the presence of the significant difference within the teachers' estimation on the three dimensions, due to Education and Training Quality Authority estimation variable, that teacher belongs to. The dimensional comparison of this variable shows an existence of statistically significant differences for the benefit of the excellent schools against satisfactory and inadequate schools in both dimensions teaching performance quality and professional development and against inadequate schools in system implementation mechanism dimension. It came in favor of good schools against inadequate schools, in the perspective of three dimensions, and for the benefit of satisfactory schools against inadequate schools, in the dimension of teaching performance quality and professional development. The study also showed that the most important challenges that face the implementation of teacher performance evaluation system, from the teacher perspectives are: 1) weakness of evaluator, which negatively affects the overall evaluation process. 2) The challenges of system component itself where it does not meet the educational quality requirements, in which self-directed professional development considered the major factor in the improvement process. The majority of teachers recommend that in order to have a better implementation of the system; there is a need to design continuous professional training program to improve teaching efficiency and evaluation process for both teachers and evaluators.