A Serrano pepper (Capsicum annuum) is a type of chili pepper that originated in the mountainous regions of the Mexico.

Young Serrano peppers are green, but the color at maturity can vary from red, brown, orange, to yellow. They are generally between 1 and 4 inches long (2.5 to 10 cm) and around ½ inch (1 cm) wide. They are typically not dried because of their thickness.

Serranos are in the middle of the Scoville scale (created in 1912), which measures how hot peppers are. They are below Cayenne and Tabasco pepper and above Wax and Jalapeño Peppers.