Kopi luwak, or civet coffee, refers to the beans of coffee berries once they have been eaten and egested by the Asian palm civet (Paradoxurus hermaphroditus). The name is also used for marketing brewed coffee made from the beans.

Producers of the coffee beans argue that the process may improve coffee through two mechanisms, selection and digestion. Selection occurs if the civets choose to eat coffee berries containing better beans. Digestive mechanisms may improve the flavor profile of the coffee beans that have been eaten. The civet eats the berries for the beans' fleshy pulp, then in the digestive tract, fermentation occurs. The civet's proteolytic enzymes seep into the beans, making shorter peptides and more free amino acids. Passing through a civet's intestines the beans are then defecated with other fecal matter and collected.

The traditional method of collecting feces from wild civets has given way to intensive farming methods in which civets in battery cage systems are force fed the coffee beans. This method of production has raised ethical concerns about the treatment of civets due to "horrific conditions" including isolation, poor diet, small cages and a high mortality rate. A 2013 BBC investigation of intensive civet farming in Sumatra found conditions of animal cruelty. Intensive farming is also criticised by traditional farmers because the civets do not select what they eat, so the beans are of poor quality compared to beans collected from the wild. According to an officer from the TRAFFIC conservation programme, the trade in civets to make kopi luwak may constitute a significant threat to wild civet populations.

Although kopi luwak is a form of processing rather than a variety of coffee, it has been called the most expensive coffee in the world with retail prices reaching €550 / US$700 per kilogramme. The price paid to collectors in the Philippines is closer to US$20 per kilogramme. The price of farmed (considered low-grade by connoisseurs) kopi luwak in large Indonesian supermarkets is from US$100 per kilogramme (five times the price of a high quality local arabica coffee). Genuine kopi luwak from wild civets is difficult to purchase in Indonesia and proving it is not fake is very difficult - there is little enforcement regarding use of the name "kopi luwak", and there's even a local cheap coffee brand named "Luwak", which costs under US$3 per kilogramme but is occasionally sold online under the guise of real kopi luwak.

An investigation by People for the Ethical Treatment of Animals (PETA) Asia found fraud to be rife in the kopi luwak industry, with producers willing to label coffee from caged civets with a "wild sourced" or similar label. A BBC investigation revealed similar findings.

Kopi luwak is produced mainly on the islands of Sumatra, Java, Bali and Sulawesi in the Indonesian Archipelago. It is also widely gathered in the forest or produced in the farms in the islands of the Philippines (where the product is called kape motit in the Cordillera region, kape alamid in Tagalog areas, and kape melô or kape musang in Mindanao island), and in East Timor (where it is called kafé-laku). Weasel coffee is a loose English translation of its Vietnamese name cà phê Chồn, where popular, chemically simulated versions are also produced.