Time is a significant parameter of effective educational administration. However, the time management of school principals is not trouble free and is influenced by many factors. As these factors are minimized, so the time management is improved. The minimizing of factors is achieved with practices of time management which differ toward their prioritization and adoption by the principal of each educational unit. At the beginning, this article refers the importance of time as a parameter of effective administration. Then, we discuss for the factors that affect the organization of working time of principals. Final, the management practices of time are quoted which contribute to the greatest effectiveness of units’ principals.