Squamous non-keratinizing epithelium is a type of tissue lining found in various parts of the body, including the oral cavity, pharynx, larynx, esophagus, and vagina.

Unlike the keratinizing type, this epithelium does not produce keratin, a protein that gives the skin its toughness and resistance to abrasion. The cells in squamous non-keratinizing epithelium have a flat, thin shape and lack the granular layer present in keratinizing epithelium.

The function of this tissue is mainly to provide a protective barrier against physical, chemical, and microbial damage while allowing for the exchange of molecules and nutrients between the underlying tissues and the external environment. It also plays a role in the secretion and absorption of substances in certain organs, such as the vagina.