In this paper, we evaluate the impact of the education foundation law in the management system of the private Indonesian Islamic school. Islamic schools or madrasas are the goal of the Muslim community to educate their children where Islamic knowledge and sciences technologies are combined. The private madrasas were initiated, established and organised by the governing boards. Rapidly growing of the private madrasa but lack of management system makes the Indonesian government to stipulate law number 16 of 2001 and law number 28 of 2004. A total of 251 respondents from various foundations among six cities in Indonesia were contacted and interviewed. Instrument analysis was performed using the Rasch model approach through the Winsteps program. We observe that three groups of respondents have the same characteristics of answers. It indicates the tendency of respondents to more agree and practice the mentioned items. The respondents were found to face great difficulties when answering dual positions and authority of the governing boards. We conclude a small impact of the applicable law in the management system of the private madrasa.