This study aimed at presenting how the standards of the school performance assessment should be improved in the schools in the Sultanate of Oman based on light of some word and Arab experiences and the result of the field study.That was by studying the theoretical basics and the world models used to assessment school performance. In order to achieve that the Standards of school performance Assessment were examined in the schools in the sultanate of Oman with a study sample through a field study using a questionnaire as a tool divided into two parts. The first part contains four chapter;, the first, the second, the third, and the fourth .It also represents the degree of applying assessment tools at schools in the Sultanate of Oman which are applied to improve the performance in four areas: (School administration, education, learning, and the tools) while the second part presented the difficulties that may hinder the application of the standards of school performance.The questionnaire was distributed over (500) person.- the sample of the study was as follows: (110) School Head Master, and (390) Senior Teachers. statistical analysis of the data was done by using arithmetic means, standard deviation, and rating by order of importance. The most important results of the field study are: 1- Overall estimation of the study about the implementation of the performance assessment standards at schools in the Sultanate of Oman especially the schools that applied the system of improving school performance has greatly succeeded and this was assured by the evaluative study at present but will never present inclusion of other fields to the school performance assessment process and this is what the present study investigated. The study also pointed out that the aims of the system are clear and satisfactory to the evaluators .Moreover, school and the local community should establish mutual relations and foster for the training of the school personnel. Due care should be given to analysis of the curriculum and ensure its assessment and to what extend it meets the needs of the students. 227 2- The total estimation of the study sample persons about the degree of applying school performance tools at schools in the Sultanate of Oman especially those schools that applied the system of improving school performance were at average level. 3-The total estimation of the sample persons of the difficulties which may face applying the standards of the school performance standards at schools in the Sultanate of Oman applying the system of developing the school performance were middle standard ones. According to the study analysis and other countries experiences in the field of evaluating the school performance in the school in the Sultanate of Oman, and also the field study results, the study arrived at a conception on how to improve the performance tools between the school and the local of community through training and analyzing the curriculum and evaluating it. in addition, the difficulties and problems that face the implementation should be addressed and studied.