A sunn pest is an insect belonging to a group representing several genera of the 'shield bug' (Scutelleridae) and 'stink bug' (Pentatomidae) Families, with the species Eurygaster integriceps being the most economically important. Sunn pests are found in parts of North Africa, throughout West Asia and many of the new independent states of Central Asia.

The sunn pest is one of the most serious pests of wheat and barley in West Asia, where over $42 million (U.S.) is spent for its control. Yield loss from its damage has been estimated at 20-30% in barley and 50-90% in wheat. This insect damages these crops by feeding on leaves, stems and grains. During feeding they also inject chemicals that greatly reduce the baking quality of flour made from damaged wheat. If 2-3% of the grain is damaged, entire lots may be ruined because the flour will be unpalatable and the bread will not rise. Heavy attack causes wheat stems to break before harvest.

Large areas of wheat sometimes remain unharvested because sunn pest damage is so severe. These insects also attack barley, though damage is usually low. Large outbreaks of sunn pests generally occur every 6 to 8 years and can potentially cause yield losses of tens of millions of dollars.