The Brassicales are an order of flowering plants, belonging to the eurosids II group of dicotyledons under the APG II system. One character common to many members of the order is the production of glucosinolate (mustard oil) compounds. Most systems of classification have included this order, although sometimes under the name Capparales (the name chosen depending on which is thought to have priority).

The order typically contains the following families:

  • Akaniaceae
  • Bataceae – salt-tolerant shrubs from America and Australasia
  • Brassicaceae – mustard and cabbage family; may include the Cleomaceae
  • Capparaceae – caper family, sometimes included in Brassicaceae
  • Caricaceae – papaya family
  • Gyrostemonaceae
  • Koeberliniaceae
  • Limnanthaceae – meadowfoam family
  • Moringaceae – thirteen species of trees from Africa and India
  • Pentadiplandraceae
  • Resedaceae – mignonette family
  • Salvadoraceae
  • Setchellanthaceae
  • Tovariaceae
  • Tropaeolaceae – nasturtium family

Under the Cronquist system, the Brassicales were called the Capparales, and included among the "Dilleniidae". The only families included were the Brassicaceae and Capparaceae (treated as separate families), the Tovariaceae, Resedaceae, and Moringaceae. Other taxa now included here were placed in various orders.

The families Capparaceae and Brassicaceae are closely related. One group, consisting of Cleome and related genera, was traditionally included in the Capparaceae but doing so results in a paraphyletic Capparaceae. Therefore, this group is generally now either included in the Brassicaceae or as its own family, Cleomaceae.