Eurydema ornata can reach a length of 7–8 millimetres (0.28–0.31 in). The body has gray or bright red colors, with black markings. Sometimes it shows the red patches coloured white and yellowish-green. This shield bug sucks the sap of plants, especially crucifers (Brassicaceae family), such as cabbage, cress and radish. It may become a parasite that can damage crops. It overwinters as an adult. The nymph is pale yellow and orange with dark brown or black pronotum and markings on the dorsal side of the abdomen.