This survey aims at investigating the administrative supervisor's role and how important it is and his practice of this role from the perspective of the basic schools principals and their assistants, especially if there are statistically significant differences at level (a=0.05) referred to the variables of sex, profession, experience years and academic qualifications, and set up new suggestions that emphasize the role of the administrative supervisor. Towards that end, the relevant literature was traversed. Drawing on relevant literature, research studies and a pilot study the researcher developed a 59-item questionnaire that was subject to face validity and reliability tests. The questionnaire is divided into five dimensions, namely: planning, organizing, supervising, training, evaluating. A multistage sample consisting of (287) is selected. The data is statistically treated using percentages, means, ranking, Ttest, One Way ANOVA and Scheffe Test. Prominent among the results are: 1. The administrative supervisor's role is extremely important and its practice is in the middle average from the perspective of the basic schools principals and their assistants. 2. There are no statistically significant differences at level (a=0.05) referred to the variable of sex in the field of importance in all aspects except in planning and evaluating in favor of females. 3. There are no statistically significant differences at level (a=0.05) referred to the variables of profession, experience years and academic qualifications in the field of importance in all aspects. 4. There are statistically significant differences at level (a=0.05) referred to the variable of sex in favor of male in the field of practice in all aspects. 5. There are no statistically significant differences at level (a=0.05) referred to the variables of profession, or academic qualifications in the field of practice in all aspects. 6. There are no statistically significant differences at level (a=0.05) referred to the variable of experience years in the field of practice in aspect of planning. 7. There are statistically significant differences at level (a=0.05) in the field of practice referred to the variable of experience years in the field of organizing, supervising and evaluating in favor of those who have less than five years and in the training aspect for those who have more than seven years. In analyzing the literature review and the outcomes of the field survey, this study provides many recommendations; the most important are mentioned as following: 1. Decrease the number of the schools that the administrative supervisor supervises them. 2. The administrative supervisor should attend courses in the aspects of planning, organizing, supervising, training and evaluating. 3. Enabling them to know all about their roles in the aspects of planning, organization, supervising, training and evaluating. Also, the survey includes other suggestions to conduct other surveys on the role of the administrative supervisor in the Sultanate of Oman with regard to other aspects and variables.