Linum campanulatum is a perennial plant belonging to the Linaceae family. Linum campanulatum reaches on average 10–30 centimetres (3.9–11.8 in) in height. The short stem is perennial, woody and glabrous, with long herbaceous annual branches. Leaves are alternate, up to 4 cm long and 1 cm wide. The shape of lower cauline leaves is quite variable. Usually they are obovate-obtuse, but in some cases may be spatulate-lanceolate. The upper cauline leaves are gradually reduced in width to become almost linear.