Pixie cup may refer to:
- Fungi
- Geopyxis carbonaria, fungus also known as a "pixie cup"
- Geopyxis vulcanalis, fungus commonly known as the "vulcan pixie cup"
- Scutellinia scutellata, fungus also known as the "eyelash pixie cup"
- Lichen
- A number of species of the lichens Cladonia (cup lichen)
- Cladonia asahinae, lichen commonly known as "pixie cup lichen"