This study focuses on one of the legal maxims of Islamic jurisprudence, "The Maxim of Committing the Lesser of Two Harms: The Case of al-jihad". The study is aimed at investigating the meaning of legal maxims in Islamic jurisprudence. The study examines the definition of "al-darar" (the harmful) and its regulations and other related Islamic legal maxims and its evidences from the Qur'anic text and Prophetic Sunna. The study highlights the fact that removing or preventing harm is one of the main objectives of Islamic law. This study also examines some of the Islamic jurisprudential practices for this maxim in some issues of Al-jihad such as attacking Non-Muslims while they hold Muslim prisoners as human shield, paying tax to Non-Muslims in a situation of Muslim weakness, the legality of seeking military help from Non -Muslims in jihad, compulsory military conscription in time of war, martyrdom operations and committing suicide to protect the secrecy of Al-mujahidin (Muslim fighters). In this study, the researcher adopted two methodologies, i.e., the inductive method which is based on the collection of the relevant legal text or evidences from Qur'an and Sunna supported by the classical and modern Muslim scholar's opinions which relate to the subject matter. In this study, the researcher used the analytical method in order to analyze the legal texts from juristic point of view. Eventually, the researcher has arrived at the conclusion that some of the issues discussed in the study are very intricate and complex to determine the right opinion that pleases Allah, unless we do thorough investigations.