Divorce according to Islamic law can occur in a variety of forms, some initiated by a husband and some by a wife. The main categories of Islamic customary law are talaq (repudiation), khulʿ (mutual divorce) and faskh (dissolution of marriage before the Religious Court). Historically, the rules of divorce were governed by sharia, as interpreted by traditional Islamic jurisprudence, though they differed depending on the legal school, and historical practices sometimes diverged from legal theory.

In modern times, as personal status (family) laws have been codified in Muslim-majority states, they generally have remained "within the orbit of Islamic law", but control over the norms of divorce shifted from traditional jurists to the state.

According to the Quran, marriage is intended to be permanent, as indicated by its characterization as a "firm bond" and by the rules governing divorce. The relationship between the spouses should ideally be based on love (30:21) and important decisions concerning both spouses should be made by mutual consent. When marital harmony cannot be attained, the Quran allows spouses to bring the marriage to an end, although this decision is not to be taken lightly, and the families of the spouses are called upon to intervene by appointing arbiters to attempt a reconciliation. The Quran also sets waiting periods to discourage hasty divorces. For a menstruating woman, the waiting (Iddah) period before the divorce is finalized, as three monthly periods. For post-menopause women and non menstruating women, the waiting period is three months. This is to ensure the woman is not pregnant and thus guarantee the paternity of future children she may have with her next husband, and to give the husband time to reconsider his decision. Moreover, a man who vows not to have sexual intercourse with his wife, which would lead to automatic divorce, is allowed a four-month period to break his oath.

The Quran substantially reformed the gender inequity of divorce practices that existed in pre-Islamic Arabia, although some patriarchical elements survived and others flourished during later centuries. Before Islam, divorce among the Arabs was governed by unwritten customary law, which varied according to region and tribe, and its observance depended on the authority of the individuals and groups involved. In this system, women were particularly vulnerable. The Quranic rules of marriage and divorce provided a fixed set of norms for all Muslims, backed by divine authority and enforced by the community. The early Islamic reforms included giving the wife a possibility to initiate divorce, abrogation of the husband's claim to his wife's property, condemnation of divorce without compelling reason, criminalizing unfounded claims of infidelity made by the husband, and institution of financial responsibilities of the husband toward his divorced wife. In pre-Islamic times, men kept their wives in a state of "limbo" by continually repudiating them and taking them back at will. The Quran limited the number of repudiations to three, after which the man cannot take his wife back unless she first marries another man. Additionally, the pre-Islamic bridewealth (mahr), which was paid by the groom to the bride's family, was transformed into a dower, which became property of the wife, though some scholars believe that the practice of giving at least a part of the mahr to the bride began shortly before the advent of Islam.

The subject of divorce is addressed in four different surahs of the Quran, including the general principle articulated in 2:231:

If you divorce women, and they reach their appointed term, hold them back in amity or let them go in amity. Do not hold them back out of malice, to be vindictive. Whoever does this does himself injustice.

Classical Islamic law is derived from the scriptural sources of Islam (Quran and hadith) using various methodologies developed by different legal schools. It was historically interpreted by jurists (muftis) who were expected to give a legal opinion (fatwa) free of charge in response to any query. Family disputes are handled in a religious courts presided over by a judge (qadi) who had enough legal education to decide some legal questions and queried a mufti if faced with a difficult legal issue. The judges were active members of the local community and were also involved in informal arbitration, which was the preferred method of resolving disputes. In court proceedings, they mediated between the letter of the law and exigences of the local social and moral concerns, with the overarching aim of ensuring social harmony. Actual legal practice sometimes deviated from the precepts of the legal school that was dominant in the area, at times to women's benefit and at times to their disadvantage. Members of all social classes and their witnesses argued their cases in court without professional legal representation, though members of the upper class generally did so through a representative. Women were commonly involved in litigation, usually as plaintiffs, were assertive in arguing their cases, and they were often treated sympathetically by the judge. According to legal doctrine, a woman's testimony in some areas of law carried half the weight of that of a man, though available evidence suggests that practical effects of this rule were limited and the legal standing of women in pre-modern Islam was comparable to or higher than that of their European contemporaries.

The term talaq is commonly translated as "repudiation" or simply "divorce". In classical Islamic law it refers to the husband's right to dissolve the marriage by simply announcing to his wife that he repudiates her. Classical jurists variously classified pronouncement of talaq as forbidden or reprehensible unless it was motivated by a compelling cause such as impossibility of cohabitation due to irreconcilable conflict, though they did not require the husband to obtain court approval or provide a justification. The jurists imposed certain restrictions on valid repudiation. For example, the declaration must be made in clear terms; the husband must be of sound mind and not coerced. Upon talaq, the wife is entitled to the full payment of mahr if it had not already been paid. The husband is obligated to financially support her until the end of the waiting period or the delivery of her child, if she is pregnant. In addition, she has a right to child support and any past due maintenance, which Islamic law requires to be paid regularly in the course of marriage.