Korean chili peppers or Korean hot peppers, also known as Korean red, Korean dark green, or Korean long green peppers according to color (ripening stages), are medium-sized chili peppers of the species Capsicum annuum. The chili pepper is long, slender and mild in flavor and spice. Green (unripe) chili peppers measure around 1,500 Scoville heat units.

Gochugaru or Korean chili powder, is chili powder or flakes made from these peppers.

In Korean, the chili peppers are most often called gochu (고추), which means "chili pepper". Green ones are called putgochu (풋고추), and red ones are called honggochu (홍고추).

Chili peppers, which originated in the Americas, were introduced by Portuguese traders to Korea, via Japan, in the late 16th century. There is mention of chili pepper or mustard in Korea traced to Japan found in Collected Essays of Jibong, an encyclopedia published in 1614. Farm Management, a book from around 1700, discussed the cultivation methods of chili peppers.

Gochugaru, also known as Korean chili powder, is dried chili powder or flakes used in Korean cuisine. The name gochugaru is derived from Korean gochutgaru 고춧가루, from gochu (고추) 'chili pepper' and garu (가루) 'powder'. In English, gochugaru usually refers to the seedless, Korean variety of chili powder. It has a vibrant red color, the texture may vary from fine powder to flakes, and the heat level from mildly hot to very hot. Traditionally made from sun-dried Korean red chili peppers (태양초; taeyangcho), gochugaru has a complex flavor profile with spicy, sweet, and slightly smoky tastes. Gochugaru made from Cheongyang chili pepper is finer and hotter.

The use of red gochu pepper to ward off misfortune has been a shamanistic folk practice used in many aspects of Korean life.

From the National Folk Museum of Korea:

Gochu, or red pepper, is used to cleanse impurities and to chase away evil spirits in the event of an illness or the birth of a son.