The main source of Islam is the Holy Qur'ān. Qirā’a is the branch of science that deals with the different ways of reciting the words of the Qur'ān. For this reason, the science of qirā’a has a special place and importance among the basic Islamic sciences. The fact that the Qur'ān ranks first among the primary evidences in Islamic jurisprudence methodology has made it directly related to the science of qirā’a. At the beginning of Islam, the verses revealed were transmitted firsthand by the Prophet (PBUH) to his companions, who in turn would teach these verses to others. The differences in reciting that existed in this process led to the types of qirā’a called 'seven ahruf/letters'. Believers would first learn the different qirā’āt that they heard from the Prophet (PBUH) and then pass them on to the others. However, in addition to the authentic qirā’āt, the unauthentic qirā’āt that emerged over time directly affected the Islamic legal doctrine. Especially the differences in the most accurate understanding of the divine word led to the emergence of differences of opinion among Islamic jurists. This, in turn, was the source of the divergence of jurisprudential groups. These divergences between the groups based on the differences in qirā’a have come to the agenda depending on the issues of Islamic law, sometimes usūl and sometimes furū’. These debates have led to different jurisprudential approaches depending on the different interpretations of the verses, which has led to mental turmoil among Muslims. In this study, the impact of qirā’a differences on Islamic legal doctrine is analyzed. In this context, the issue of intercourse with a woman after menstruation, one of the issues of jurisprudence, is discussed., Regarding this, in the text the concept of qirā’a, its types, and the reasons for the emergence of qirā’a differences are first evaluated. For a better understanding of the issue, the approaches of the four fiqh schools to the differences of qirā’a are also examined in a general way. Then, the jurisprudential aspect of the concept of menstruation, the way it is expressed in the verse, and the differences of qirā’a on the related verse are examined, and the legal consequences that arise due to these different qirā’āt are explained. As far as can be detected in the process, most of the studies in the field of basic Islamic sciences are carried out in the form of subject analysis under a specific discipline. Unlike the general studies in the literature, in this research, a fundamental issue related to Islamic law and qirā’a, which is among the basic disciplines of Islamic sciences, has been addressed, which reveals the strong bond and interaction between the two disciplines. In order to have a better understanding of the subject of the present research, special attention has been given to include the fundamental sources of the science of qirā’a along with Islamic law.