Pterygium is a common ocular surface disease in China, with a high prevalence rate of 2% to 5% and a total of 20 to 50 million patients. Although the disease seems to be simple, ophthalmologists face a lot of confusion due to its complex pathogenesis, many surgical methods, various drugs used, and high recurrence rate after surgery. We will briefly discuss the pathogenesis and recurrence of the disease. Research on the pathogenesis of pterygium involves epidemiology, pathology, anatomy, molecular biology, immunology, virology, and genetics, and there are both consistent and inconsistent findings. For example, epidemiological findings are consistent in that race, sex, age, genetics, and geographic variation in pterygium are associated with latitude, work, and living environment, but the prevalence in men and women is controversial among scholars. The pathology of pterygium has been found to include a mechanism of hypersensitivity reaction, but there is disagreement as to whether type I, III, and IV hypersensitivity reactions exist singly or in combination. Molecular biology studies have shown that pterygium exhibits tumor-like properties, but it is not clear whether it is an imbalance between oncogenes and oncogenes or a mutation in oncogenes. In addition, the cell cycle of pluripotent stem cells or progenitor cells in the head of pterygium is disturbed, telomerase activity is enhanced, apoptosis of corneal epithelial cells is enhanced, anti-apoptosis of pterygium epithelial cells is diminished, matrix metalloproteinase and its inhibitor 1 are imbalanced in pterygium epithelial cells, tear film stability is decreased in pterygium patients, and overexpression of various cytokines or growth factors are associated with the development of pterygium. The causal relationship between the development of pterygium and the development of pterygium has not yet been established. Genetic studies have found that some patients have a familial predisposition, but no consensus has been reached. Epidemiological studies have shown that environmental factors, such as ultraviolet radiation, are important predisposing factors for pterygium. UV light from sunlight has two main induction effects: 1. UV light causes degeneration of the bulbar conjunctiva, oncogene p53 mutation in conjunctival epithelial cells, decreased expression of cell cycle regulatory gene p21/p27kip1 leads to disruption of the bulbar conjunctival epithelial cell cycle, abnormal increase of telomerase activity in conjunctival epithelial cells, and upregulation of apoptosis regulatory gene Bc1/Bax ratio leads to degenerative conjunctival epithelial cells with unlimited proliferative activity; 2. 2 UV light causes disruption of the corneal rim barrier, imbalance of matrix metalloproteinases and their inhibitors, degradation of the anterior corneal elastin layer, invasion of proliferative degenerative conjunctival epithelial cells into the cornea, and progressive hypertrophy of the hyperplastic bulbar conjunctiva by the action of growth factors and/or cytokines such as fibroblast growth factor, vascular endothelial growth factor, and epidermal growth factor. If the stimulus disappears, the hyperplasia of the bulbar conjunctiva stagnates in the quiescent phase, and if the stimulus persists, it progresses to the active phase. In conclusion, it can be inferred that the main cause of pterygium is environmental factors (ultraviolet light), the most important mechanism is the destruction of the epithelial (stem cell) barrier at the corneal limbus, and the most basic pathology is the degeneration and hyperplasia of the conjunctiva. The recurrence of postoperative pterygium is a problematic issue in the surgical treatment of this disease in China, and the recurrence rate is high, ranging from 20% to 70% in China and 24% to 89% abroad. The recurrence rate of primary pterygium is low, while the recurrence rate of recurrent pterygium is high. The mechanism of postoperative pterygium recurrence has been less studied. The recurrence of postoperative pterygium is not only related to the surgical approach, thoroughness of excision, perioperative medication, and elimination of postoperative irritants, but also to individual differences and the status of the lesion itself. There is an important correlation between the surgical skill of the ophthalmologist and the rate of postoperative pterygium recurrence, and skilled surgery will significantly reduce the recurrence rate.