Kiesselbach's plexus is a vascular network of four or five arteries in the nose. It supplies the nasal septum. The arteries anastomose to form the plexus. It lies in the anterior inferior part of the septum known as Little's area, Kiesselbach's area, or Kiesselbach's triangle. It is a common site for nosebleeds.

A nosebleed, also known as epistaxis, is bleeding from the nose. Blood can also flow down into the stomach and cause nausea and vomiting. In more severe cases, blood may come out of both nostrils. Rarely, bleeding may be so significant that low blood pressure occurs. Blood may also come up the nasolacrimal duct and out from the eye.

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