AIM:To evaluate the long-term effect of laser peripheral iridoplasty (LPIP) on primary acute angle-closure glaucoma(PAACG) with extensive goniosynechia. METHODS:Retrospective case series.33 PAACG patients who had extensive goniosynechia were given LPIP treatment.The clinical responses of each patient,especially in their lOP reduction and goniosynechia changes,were tracked closely,and any complication from the laser treatment was recorded and studied.An lOP lower than 21mmHg with or without 3 kinds of topical medication was defined as a successful outcome. RESULTS:ln 21-37 months follow-up, lOP were successfully controlled in 24 eyes,15 of which were given 1 or 2 topical medication. 9 eyes finally failed to respond to LPIP therapy and were given trabeculectomy,6 of which received trabeculectomy 3 days after LPIP and 3 of which received the same treatment 18 days,42 days and 9 months after LPIP,respectively. After LPIP, iridocomeal angles of 27 eyes were observed to be widened by certain degrees in a short period of time,6 eyes suffered goniosynechia development during 6-12 months follow-up.3 eyes developed nuclear cataract during the follow-up,1 of which was performed phacoemulsification 3 years after LPIP. CONCLUSION:LPIP appeared to be an effective treatment for acute angle-closure glaucoma with extensive goniosynechia.Certain eyes may suffer increase in IOP and development of iris peripheral anterior synechiae,therefore inspection should be applied carefully to these patients.