Flammulina filiformis is a species of edible mushroom in the family Physalacriaceae widely cultivated and consumed throughout East Asia. It is commonly known as the enoki mushroom or enokitake. The genus name Flammulina derives from the Latin flamma, meaning “flame,” referring to the orange-brown coloration seen in wild forms of related species, while the species epithet filiformis means “thread-like,” describing the long, slender stems that characterize cultivated specimens. Historically, cultivated enoki mushrooms were often identified as Flammulina velutipes, but taxonomic and molecular studies have clarified that the cultivated East Asian form is correctly classified as Flammulina filiformis. In Japanese cuisine it is widely known as enokitake (エノキタケ).

In nature, Flammulina filiformis grows on decaying hardwood logs, particularly elm and related tree species, during cool seasons. Wild mushrooms have shorter stems and golden caps, whereas cultivated varieties are grown in controlled environments with limited light and high carbon dioxide levels. These conditions produce the familiar long, thin white stems and small caps that are typical of commercially grown enoki mushrooms. The cultivation process allows year-round production and has made the mushroom a staple ingredient in many East Asian dishes.

As a food source, Flammulina filiformis is valued for its mild flavor and crisp texture. It is commonly used in soups, hot pots, stir-fries, and noodle dishes. In Japanese cuisine it frequently appears in nabe hot pot dishes and miso-based soups, while in Korean and Chinese cooking it is incorporated into broths, vegetable mixes, and wrapped meat dishes. The mushrooms soften slightly when cooked but retain a characteristic delicate crunch. In China and Taiwan, they are jokingly referred to as "see you tomorrow" because they are often not fully digested and appear in the stool intact the next day.

Nutritionally, Flammulina filiformis is low in calories and provides dietary fiber, B vitamins such as niacin and riboflavin, and minerals including potassium and phosphorus. It also contains a range of bioactive compounds that have attracted scientific interest. These include polysaccharides such as beta-glucans, ergothioneine (a sulfur-containing antioxidant amino acid derivative), and small fungal immunomodulatory proteins. Experimental studies have investigated these compounds for potential antioxidant, immune-modulating, and cholesterol-lowering properties. Flammulina filiformis also contain flammutoxins, which are denatured by normal cooking.