Differences in concepts among the existing religious schools are a reality, which cannot be denied by anyone. Differences and even clashes of concepts occur in almost several aspects of religious life, both in the field of monotheism and the concept of regulating life in the field of muamalah. This, in practice, often triggers very sharp conflicts between Muslims of different sects. From this fact, a breakthrough is needed to try to provide alternative ideas and solutions for the implementation of the Isbath session which has always been carried out after sunset at the beginning of the month of Ramadan, Shawwal, and Dzulhijjah. This study aims 1. To uncover the background or factors that influence as well as to examine and analyze the regulation on the determination of the beginning of the month of Qamariyah 2. To be able to understand the weaknesses of the regulation technique to determine the beginning of the month of Qamariyah 3. To reconstruct the technique of regulation of the determination of the beginning of the month of Qamariyah. This study uses a juridical-sociological approach. The research specification is descriptive analysis. The results of the research and discussion show that Article 52A of Law no. 3 of 2006 concerning the isbath trial, reads “The religious court shall provide istbat testimony of the rukyat hilal in determining the beginning of the month in the Hijri year. Weaknesses of Article 52A of Law no. 3 of 2006 concerning Religious Courts, this article gives a mandate to religious courts which then the mandate is not followed up with several rules that create togetherness and conducive atmosphere for the determination, namely by combining several differences that occur, and giving birth to the minister of religion to be absolute in making decisions. Determination of the beginning of the Qamariyah month. Reconstruction of regulations for determining the beginning of the qamariyah month in Indonesia based on the value of justice, an effort to review Article 52A of Law no. 3 of 2006 concerning the Religious Courts which need to be refined with Article 52 B, Article 52 C, and Article 52 D. This is to anticipate some of the weaknesses of the article to be able to accommodate all the interests of the community and components of the Indonesian nation which are based on the values ​​of justice.