Problem Statement: “Motivation” can be defined as the action of directing human behavior in a desirable way. School principals are not only the managers who are the most responsible for the school. The vice principals who are officially charged and help the principals with the school tasks are also called school managers. School managers have a direct impact on the performance of personnel. Knowing the opinions of the managers about internal and external motivation increases the success of the educational institution. Purpose of the Study: The aim of this research was to reveal the ideas of primary and secondary school principals about motivation. The problems under review are: (1) What are the opinions of the primary and middle school principals about internal motivation?; (2) Do the opinions of the primary and middle school principals about internal motivation differentiate depending on gender, duty at school, school grade, and education level?; (3) What are the opinions of the primary and middle school principals about external motivation?; (4) Do the opinions of the primary and middle school principals about external motivation differentiate depending on gender, duty at school, school grade, and education level? Method: This study was a descriptive research study. The outcome consists of 55 randomly selected principals and deputy principals working in primary school, middle school, and high school in the center, town, and villages of Denizli Buldan. In order to gather data, a scale developed by the researchers, called “opinions of principals about internal and external motivation”, was used. In the real application of the scale, while the Cronbach Alpha value of internal motivation was 0.80, the Cronbach Alpha value of external motivation was 0.88. The total Cronbach Alpha value of the scale was calculated as 0.87. To confirm whether the allocation was normal, the Kolmogorov Simirnov test was applied. According to the result, the data was said to be normal [(K-s)-z =0.633 p=0.818]. Test T and Anova were used to analyze the data parametric tests. Findings: The principals involved in the research stated “I agree” for internal motivation with the average of 3.74, while they stated “I agree” for external motivation with an average of 4.18. Based on the feedback from the primary and secondary school principals, no meaningful difference was defined related to gender, education level, occupation, and the grade of the school. Conclusion and Recommendations: The participating primary and middle school principals said “I agree” for “internal motivation” with an average of 3.74 and “I agree” for “external motivation” with an average of 4.18. According to the results of the research, these ideas can be suggested: (1) Principals are motivated by “the feeling of achieving difficult tasks”. They should be allowed to create higher targets. (2) The principals are motivated by “team spirit at school”. Creating the principal’s own team is important, based on this result. Key words: School principal, motivation, internal motivation, external motivation, opinion.