The purpose of this randomized multi-center clinical trial is to compare the efficacy and safety of intraoperative mitomycin C(MMC),amniotic membrane transplantation(AMT) and Conjunctival Autograft(CAG) for primary pterygium surgery. The investigators will also evaluate particular risk factors related to pterygium recurrence.

Patients with primary pterygium will be randomly assigned to undertake pterygium excision followed by intraoperative mitomycin C application,amniotic membrane transplantation or conjunctival autograft in five clinical centers. Multi-center collaboration and quality monitoring will be based on a website designed for this study. The patients will be followed at least 12 months. Corneal Recurrence as the primary outcome measure, is considered as a fibrovascular ingrowth beyond the limbus with conjunctival drag.

Inclusion Criteria:

• Primary pterygium
• Willingness to participate in research project and to attend research follow-up
• Adults (age 18 to 80 years old)
• Patients must not meet any of the following exclusion criteria

Exclusion Criteria:

• Pregnant,breast-feeding women or patients with poor general health
• Patients with significant ocular or lid pathology, such as Sjogren's Syndrome, infection, exposure keratitis, glaucoma, active uveitis, retinal detachment and trauma
• Patients with previous surgery on ocular surface, such as trabeculectomy, strabismus surgery
• Patients with allergy to intraoperative or postoperative drugs, such as mitomycin C, tobramycin or local anesthetics