Cudweed is a common name for several plants in the Asteraceae family, and may refer to:
Gamochaeta, a plant genus with species in North and South America
Gnaphalium, a plant genus with species in Eurasia and the Americas
Filago, a plant genus in Eurasia and North America
Pseudognaphalium, a plant genus native to North America
Euchiton, a plant genus native to Australasia and the Pacific
Helichrysum, a plant genus occurring in Africa, Australasia and Eurasia. (e.g. Helichrysum luteoalbum, common name 'Woody cudweed')