The purpose of this study was to design a standardized scale to measure the trust in general education schools' administrations in the Sultanate of Oman as perceived by parents. The scale was designed as to be reliable and valid to an extent in which it would measure organizational trust in the field of education. After deriving criteria according to its score analyzing, also from the social significations of common culture, the study was based on five factors of organizational trust; benevolence, reliability, competence, honesty, and openness, In order to measure these factors the study depended on parents' as an external source for the organizational trust. In order to achieve the purpose of the study psychometric measure was distributed to four experimental and exploration groups/samples of different sizes from the Muscat Province have been conducted. The standardization procedure has been applied on the data collected from a sample of 1775 parents, representing the entire eleven educational regions of The Sultanate of Oman. Statistical Package for Social Sciences (SPSS) was applied in analyzing the statistical data calculation using the following methods: Factor analysis, Pearson Corrilation, Means, And Standard Deviation. The results of this study after factor analytic studies were the achievement of an operational scale that has acceptable and showed reliability between (0.85 and 0.88), supported the construct and discriminated validity of the concept. The scale consisted of (50) items that measures the parent's trust in schools' administrations in an administrative environmental workplace. The research has lead us to conclude five statistical factors above each, including (10) items in sequence as to the scale. The findings strongly indicated information that the level of trust on General Education schools administration showed high degree of trust in general. The outcome of this study provided suggestions and recommendation for use of the scale at wbat fields and for future studies.