Descurainia is a genus of plants in the family Brassicaceae which are known commonly as the tansymustards. The genus name commemorates French botanist and herbalist François Descurain (1658–1749). The plants are similar in appearance to other mustards, sending up long erect stems and bearing small yellow or whitish flowers. Many species are noxious weeds. Some species are toxic to livestock and become a nuisance when they grow in grazing fields. Plants of this genus are found worldwide in temperate regions. Descurainia sophia, (flixweed or herb sophia), is the type species of Descurainia.

Species: 47 species are accepted.

• Descurainia adenophora
• Descurainia adpressa
• Descurainia altoandina
• Descurainia antarctica – Tierra del Fuego tansymustard
• Descurainia argentea
• Descurainia artemisioides
• Descurainia athrocarpa
• Descurainia bourgaeana
• Descurainia brevifructa
• Descurainia brevisiliqua
• Descurainia browniae
• Descurainia californica – Sierra tansymustard
• Descurainia canoensis
• Descurainia cleefii
• Descurainia cumingiana
• Descurainia depressa
• Descurainia erodiifolia
• Descurainia gilva
• Descurainia gonzalezii
• Descurainia hartwegiana
• Descurainia heterotricha
• Descurainia impatiens
• Descurainia incana – mountain tansymustard
• Descurainia incisa
• Descurainia kenheilii
• Descurainia kochii
• Descurainia lasisiliqua
• Descurainia lemsii
• Descurainia longepedicellata
• Descurainia millefolia
• Descurainia myriophylla
• Descurainia nana
• Descurainia nelsonii
• Descurainia nuttallii
• Descurainia obtusa – blunt tansymustard
• Descurainia paradisa – paradise tansymustard
• Descurainia pimpinellifolia
• Descurainia pinnata – western tansymustard
• Descurainia preauxiana
• Descurainia sophia – flixweed, herb-Sophia or tansy
• Descurainia sophioides – northern tansymustard
• Descurainia streptocarpa
• Descurainia stricta
• Descurainia tanacetifolia
• Descurainia torulosa – Wind River tansymustard
• Descurainia tugayi
• Descurainia virletii