AIM:To study the curative effect,complications, safety and merit of Knife 90 and 110 of Moria M2 in excimer laser in situ keratomileusis(LASIK) for myopia. METHODS:The selected 105 cases (202 eyes) of LASIK surgery patient were divided into two groups according to the stochastic tables. Knife 90 of Moria M2 was used in 51 cases (98 eyes) of LASIK patients, Knife 110 in 54 cases (104 eyes) of LASIK patients as control.After operation, optical coherence tomography (OCT) was used to detect two groups of corneal flap thickness.Two groups of techniques were observed 1 day, 1 week, 1 month, and 3 months postoperatively with uncorrected visual acuity (UCVA), corrected visual acuity(CVA) and corneal flap shape, involution situation, complications. RESULTS:Corneal flap thickness of Knife 90 group was 118.3±15.2μm, corneal flap thickness of Knife 110 group was 130.5±17.1μm, having significant difference. Knife 90 group had not discovered interlaminar punctiform metal detritus, Kinfe 110 group had interlaminar punctiform metal detritus case (12 cases), having significant difference.The two groups were similar in form of the corneal flap, involution situation, postoperative reaction and postoperative UCVA. CONCLUSION: The LASIK efficacy and complications of Knife 90 are similar with Kinfe 110, however, Knife 90 can retain a relative thicker cornea stroma, correct higher diopter, howe less interlaminar punctiform metal detritus and complications, therefore it has better safety and adaptation range．