This study adopted Content Analysis and cited the investigating pattern of Grand Justices, Tzong-Li Sheu & Yuh-Shiou Sheu, regarding differing opinion paper of Judicial Yuan Interpretation No.596. in order to test the constitutionality of that primary and secondary school ( including vocational school ) teachers who quitted principal’s position were appointed directly to be full-time teachers, apart from the test of school teacher accreditation Committee postulated in " Teachers Law", "Education Personnel Appointment Regulations". " Fair, just and open " is the principle of hiring teachers by schools. About appointment of teachers, both teachers who quitted principal’s position and teachers who didn’t have qualification and service experience of principal could be discussed contemporaneously. Exclusive prescription made intentionally for teachers who quitted principal’s position could violate apparently justice within system and not be imperative for public goods. Strong argument of positive discrimination concerned above couldn’t be seen. Revelent regulations couldn’t pass the test of constitutional principle of equality.