The aim of this study is to develop a valid and reliable measurement tool that can be used to measure the level of school principals' micromanagement behavior. After a comprehensive literature review, a candidate item pool with 52 items was created. While writing the items, micro-manager behaviors defined in the literature were adapted to school principals. The items were submitted to the expert opinion and necessary corrections were made in the items in line with the feedback from the experts. Candidate items were applied to two different samples to carry out validity and reliability analysis. Data obtained from the first sample of 304 teachers were used for exploratory factor analysis. The second sample group consisted of 353 teachers and the data obtained from this group was used for confirmatory factor analysis and reliability analysis. The findings support the four-dimensional structure of the scale with 27 items. The first dimension was named as "unable to subordinate self (15 items)", the second dimension was "time manipulation (5 items)", the third dimension was "excessive control over methodology (4 items)" and the fourth dimension was "excessive reporting (3 items)". Findings from reliability analyses were also satisfactory. To determine the reliability of the scale Cronbach's Alpha internal consistency coefficients were calculated. It was .958 for the first factor, 0.831 for the second, 0.776 for the third and 0.743 for the fourth and 0.959 for the total scale. In this context, it can be stated that the scale is valid and reliable. It can be used to determine the level of school principals' micromanagement behavior and to associate this behavior with different organizational variables.