A niqāb, niqab, or niqaab (/nɪˈkɑːb/; Arabic: نقاب), also known as a ruband (Persian: روبند) or rubandah (روبنده), is a long garment worn by some Muslim women in order to cover their entire body and face, excluding their eyes. It is an interpretation in Islam of the concept of hijab, and is worn in public and in all other places where a woman may encounter non-mahram men. Most prevalent in the Arabian Peninsula, the niqab is a controversial clothing item in many parts of the world, including in some Muslim-majority countries.

The use of face veils has been documented in various ancient cultures, including the Byzantine Empire, Persia, and Arabia. Historical sources mention women’s practices of face veiling. Additionally, Biblical references in Genesis highlight the use of veils, indicating their significance in the cultural traditions of these regions. Coptic Orthodox Christian women traditionally wore dark garments with veils, white for the unmarried and black for the married.

While face veiling practices have ancient roots across various cultures in the Mediterranean, Middle East, and Central Asia, the modern form of niqab became more widespread particularly since the late 1970s Islamic revival, especially among Sunni Muslims throughout the Middle East and North Africa. This phenomenon was encouraged by the rise of "Petro-Islam" under the House of Saud; the propagation of hardline Sunni Islamic doctrines from the oil-producing Arab countries, beginning in earnest after the 1973 Arab–Israeli War, would quickly come to mold the Saudis' ideological response to the religious zeal that the Iranian Revolution had stirred among Shia Muslims. Sponsorship by Saudi Arabia of mosques throughout many Muslim-majority countries led to the increased adoption of Wahhabism and Salafism globally, resulting in the rise of the niqab as one of the more noticeable consequences of the Saudi strain of Islamic revivalism, which flourished greatly throughout the late 20th century. It also consolidated the newfound religious and cultural dominance of Sunni-majority Saudi Arabia over the Arab countries as a whole, effectively serving as a social countermeasure to the religious and cultural influence of Shia-majority Iran.

Since the 2000s, and particularly after the September 11 attacks in the United States, the niqab has increasingly become the subject of negative attention in the Western world, as it is commonly perceived by detractors as a visible sign of growing Islamic extremism and a rejection of Western values. For instance, in Algeria, where the presence of the niqab increased considerably in the 1990s, the Algerian public consciousness began associating the garment with the Islamists who were fighting in the Algerian Civil War; it was also protested by some Algerians as a byproduct of Saudi-backed Islamic fundamentalism—one that lacked authenticity in Algerian culture.

To varying degrees, wearing the niqab or the burqa has been banned by legislation in several countries, including a number of Muslim-majority countries. A significant amount of Muslim scholars consider the niqab as not compulsory for practicing Muslim women. Though similar, the niqab is distinct from the burqa by way of the eyes: a niqab does not cover the eyes, varies in the thickness of the material used, and has visible sleeves; but a burqa is elaborately designed with thicker material that covers the woman's entire body figure and face, lacking sleeves (i.e., keeping the entire body under the uniform cloth) and having a mesh screen to obfuscate the eyes. While the niqab is more widespread, the burqa is largely limited to Central Asia and South Asia, and is most prominent in Afghanistan.

Women who wear the niqab are often called niqābīah; this word is used both as a noun and as an adjective. However, the more correct form grammatically is منتقبة muntaqabah / muntaqibah (plural muntaqabāt / muntaqibāt) but niqābīah is used in an affectionate manner (much as with ḥijābīah versus محجبة muḥajjabah). Women in niqab are also called منقبة munaqqabah, with the plural منقبات munaqqabāt.

In pre-Islamic Arabia, face veiling was common among women of various religious backgrounds. The Roman author Tertullian, who was a Christian, described in The Veiling of Virgins the contemporary societal tendency among pagan Arabian women to cover their entire faces.

Al-Ghazali states in The Revival of the Religious Sciences that "men have always uncovered their faces throughout time, and women have always gone out in niqab." Al-Hafiz Ibn Hajar said in Fath al-Bari: “It has always been the custom of women, both in the past and in the present, to cover their faces from strangers.”