Diplotaxis siettiana, known in Spanish as jaramago de Alborán, is a species of flowering plant in the family Brassicaceae. It is endemic to Alborán Island in the western Mediterranean Sea, where it grows only around the helipad. The natural population became extinct in 1974, but the species was re-introduced from ex-situ conservation in 1999. Its natural habitat is Mediterranean-type shrubby vegetation. It is threatened by habitat loss.