Kosher wine (Hebrew: יין כשר, romanized: yáyin kashér) is wine that is produced in accordance with halakha, and more specifically kashrut, such that Jews will be permitted to pronounce blessings over and drink it. This is an important issue, since wine is used in several Jewish ceremonies, especially those of Kiddush.

To be considered kosher, Sabbath-observant Jews must supervise the entire winemaking process and handle much of it in person, from the time the grapes are loaded into the crusher until the finished wine product is bottled and sealed. Additionally, any ingredients used, including finings, must be kosher. Wine that is described as "kosher for Passover" must have been kept free from contact with leavened or fermented grain products, a category that includes many industrial additives and agents.

When kosher wine is produced, marketed, and sold commercially, it would normally have a hechsher (kosher certification mark) issued by a kosher certification agency, or by an authoritative rabbi who is respected and known to be learned in Jewish law, or by the Kashruth Committee working under a beth din (rabbinical court of Judaism).

In recent times, there has been an increased demand for kosher wines, and a number of wine-producing countries now produce a wide variety of sophisticated kosher wines under strict rabbinical supervision, particularly in Israel, the United States, France, Germany, Italy, South Africa, Chile, and Australia. Two of the world's largest producers and importers of kosher wines—Kedem and Manischewitz—are both based in the American Northeast.

The use of wine has a long history in Judaism, dating back to biblical times. Archeological evidence shows that wine was produced throughout ancient Israel. The traditional and religious use of wine continued within the Jewish diaspora community. In the United States, kosher wines came to be associated with sweet Concord wines produced by wineries founded by Jewish immigrants to New York.

Beginning in the 1980s, a trend towards producing dry, premium-quality kosher wines began with the revival of the Israeli wine industry. Today kosher wine is produced not only in Israel but throughout the world, including premium wine areas like Napa Valley and the Saint-Émilion region of Bordeaux.

It has been one of history's cruel ironies that the blood libel---accusations against Jews using the blood of murdered non-Jewish children for the making of wine and matzot---became the false pretext for numerous pogroms. And due to the danger, those who live in a place where blood libels occur are halachically exempted from using [kosher] red wine, lest it be seized as "evidence" against them.

Almost all Jewish holidays, especially the Passover Seder where all present drink four cups of wine, on Purim for the festive meal, and on the Shabbat require obligatory blessings (Kiddush) over filled cups of kosher wine that are then drunk. Grape juice is also suitable on these occasions. If no wine or grape juice is present on Shabbat, the blessing over challah suffices for kiddush on Friday night; for Kiddush on Shabbat morning as well as Havdalah, if there is no wine one would use "Chamar ha-medinah", literally the "drink of the country".