The scarlet lily beetle, red lily beetle, or lily leaf beetle (Lilioceris lilii), is a leaf beetle that eats the leaves, stem, buds, and flower, of lilies, fritillaries and other members of the family Liliaceae. It lays its eggs most often on Lilium and Fritillaria species. In the absence of Lilium and Fritillaria species, there are fewer eggs laid and the survival rate of eggs and larvae is reduced.
The lily leaf beetle is indigenous to parts of Europe and Asia. It is thought to have been introduced to North America through the importation of plant bulbs in 1943.