Thymosin is a kind of protein that is widely distributed in many tissues. It has many biological activities. Thymosin is divided into three subtypes: thymosin α, thymosin β and thymosin γ. Thymosin β4(Tβ4)is the most widely distributed in normal human body. A large number of studies have confirmed that Tβ4 has the functions of anti-inflammatory, anti-apoptosis and promoting proliferation. Ocular surface diseases are mostly related to ocular surface injury and inflammation. Therefore, promoting wound repair and healing and anti-inflammatory are the key to the treatment of ocular surface diseases. The present review mainly introduces the distribution, structure, synthesis of Tβ4 and its protective effect on ocular surface.