Kiesselbach's plexus, which lies in Kiesselbach's area, Kiesselbach's triangle, or Little's area, is a region in the anteroinferior part of the nasal septum where four arteries anastomose to form a vascular plexus of that name. The arteries are:
- Anterior ethmoidal artery (from the ophthalmic artery)
- Sphenopalatine artery (terminal branch of the maxillary artery)
- Greater palatine artery (from the maxillary artery)
- Septal branch of the superior labial artery (from the facial artery)
Ninety percent of nose bleeds (epistaxis) occur in Little's area, as it is exposed to the drying effect of inspiratory current. Alternatively, it can be argued, since most nosebleeds are provoked by nose-picking, that this very vascular area of nasal mucosa is within reach of the probing finger.
Kiesselbach's plexus is named after Wilhelm Kiesselbach (1839–1902) a German otolaryngologist. James L. Little an American surgeon, first described the area in 1879, Kiesselbach published his paper in 1884. Little described the area as being "about half an inch .... from the lower edge of the middle of the column [septum]." 
- Moore, Keith L. et al. (2010) Clinically Oriented Anatomy, 6th Ed, p.959
- Doyle, DE (Mar 1986). "Anterior epistaxis: a new nasal tampon for fast, effective control.". The Laryngoscope 96 (3): 279–81. PMID 3951304.
- Analysis of Epistaxis in Pregnancy, Little, J. L.: A hitherto undescribed lesion as a cause of epistaxis, with 4 cases, Hosp. Gaz., 6:5, March-Dec. 1879.