PURPOSE: To analyze the safety of photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) with the Nidek EC-5000 excimer laser for surgery performed from Jan 1999 to Dec 2001. METHODS: Retrospective study of excimer laser in 683 eyes: PRK was performed in 103 eyes and LASIK was performed in 580 eyes using the Nidek EC-5000 excimer laser and Moria Carriazo Barraquer microkeratome. We classified complications as intraoperative, early postoperative (30 days) and late postoperative complications. All patients were followed for at least 6 months. RESULTS: There were 15 (2.19%) intraoperative microkeratome-related flap complications, 5 thin flaps (0.73%), 4 free caps (0.58%), 3 buttonholes (0.43%), and 3 small flaps (0.43%). The most frequent early postoperative complication was dry eye with pain in 42 eyes. There were 30 cases of micro-wrinkled flaps (4.39%), 14 cases of dislocated flaps or flap striae that necessitated lifting and irrigating the flap (2.04%), 8 interface epithelial ingrowth (1.17%), 4 interface debris (0.58%), 3 haze (0.43%), 3 glare (0.43%), 2 decentered ablations (0.29%), and 2 cases of toxic keratitis (0.29%). Late postoperative complications were 98 cases of spherical equivalent refraction more than or equal to 1.00 D (14.3%) with 6 months follow-up. Reoperation was necessary in 33 eyes (4.83%). Five eyes lost 1 or more lines of preoperative best spectacle-corrected visual acuity (0.73%), and 2 eyes had keratoconus (0.29%). CONCLUSION: Refractive surgery with the Nidek EC-5000 excimer laser was safe, with few complications.