Echinocereus subinermis is a species of flowering plant in the cactus family Cactaceae, native to north, northwestern, and central Mexico. The stem is a ball with 5 to 8 prominent ribs, growing to a cylinder or cone 30 cm (12 in) tall and wide, and producing yellow flowers 8 cm (3 in) long in early summer. In cultivation in temperate regions it requires the protection of glass with heat. It has gained the Royal Horticultural Society's Award of Garden Merit.