Sarepta mustard is a one-year-old plant, reaching height of 40-100 cm, with a tap weak root. Stem leaves are located on an erect, branching stem. They are decreasing upward, while the blade is not divided a lot, and the petiole is shortened. At the bottom, the leaves are alternate, petiolate, lyrate, green, but at the very top they are whole, sessile. Leaves are not clasping and grey-coloured.
The seeds are located in thin pods with a sharp beak. The pods of Sarepta mustard grow sideward from the stem at a little acute angle, not perpendicular and not pressed against it. The size of the pod varies from 3 cm to 6 cm. Seeds ripen in August. The size of the seed is about a millimeter or slightly larger, and the color varies from yellow to reddish-brown.