The current study aimed to determine the level of administrative competence among principals of basic education schools (5-10) in the Sultanate of Oman, determine the degree of effectiveness of the professional performance of teachers in those schools, and identify whether there are statistically significant differences at the level of significance (α ≥ 05) between the arithmetic means is attributed to the following demographic study variables: (gender, educational qualification, and years of experience) in each of the study variables: the level of administrative competence and the effectiveness of the professional performance of teachers, in addition to knowing whether there is a relationship between these two variables