The function of Epithelial Tissue are:

1.  Covering: The outer layers such as buccal cavity, and the inner lining of stomach are covered by such tissues.
2. Protection: Some tissues found in the outer layer of eyes are protective.
3. Secretion: Some cells possess glands in them and secrete various kind of enzymes.
4.  Excretion: Some tissues are responsible for excretion of unnecessary substances. The tissues found in kidneys and excretory in function.
5.  Absorption: Some tissues found in the inner lining of the small intestine are absorptive in their function.