Marzipan is a confection consisting primarily of ground almonds and sugar that derives its characteristic flavor from bitter almonds, which constitute 4% to 6% of total almond content by weight. Some marzipan is also flavored with rosewater.

Marzipan is often made into sweets: common uses are marzipan-filled chocolate and small marzipan imitations of fruits and vegetables. It is also rolled into thin sheets and glazed for icing cakes and is traditionally used in wedding cakes, Christmas cakes, and stollen. In some countries marzipan is shaped into small figures of animals, such as pigs, as a traditional treat for New Year's Day. Marzipan is also used in Tortell, and in some versions of king cake eaten during the Carnival season.

In Italy, particularly in Palermo, marzipan (marzapane) is often shaped and painted with food colorings to resemble fruit - Frutta martorana - especially during the Christmas season. In Portugal, traditional marzipan (maçapão) fruit shaped sweets made in the Algarve region are called morgadinhos

Although it is believed to have originated in Persia (present-day Iran) and to have been introduced to Europe through the Turks, there is some dispute between Hungary and Italy over its origin. Marzipan became a specialty of the Baltic Sea region of Germany. In particular, the city of Lübeck has a proud tradition of marzipan manufacture (Lübecker Marzipan). The city's manufacturers like Niederegger still guarantee their Marzipan to contain two thirds almonds by weight, which results in a juicy, bright yellow product.

Historically, the city of Königsberg in East Prussia was renowned for its Marzipan production. Today, the term Königsberger Marzipan refers to a special type of Marzipan in Germany.

Under EU law, marzipan must have a minimum almond oil content of 14% and a maximum moisture content of 8.5%. Optional additional ingredients are rosewater, honey, pistachios, preservatives, and sometimes hazelnut. In the U.S., marzipan must include at least a quarter almonds by weight, otherwise it is considered to be almond paste. However, in Sweden and Finland "almond paste" refers to a marzipan that contains 50% ground almonds, i.e. a much higher quality than regular marzipan.