AIM:To identify the reasons for myopia patients not suitable for laser in situ keratomileusis(LASIK)after preoperative assessment.METHODS:Two thousand eight hundred ninety-one myopia patients were examined.824 cases of them did not undergo LASIK,the reasons were analyzedRESULTS:A total of 297 patients(36.0%)were insufficient of the corneal thickness ;194 patients(23.5%)had some apprehension about the surgery ;96 patients(11.6%)had a larger pupil ;50 patients(6.1%)had a larger height of the corneal anterior and posterior surface;the corneal curvature of 46 patients(5.6%)was higher;43 patients(5.2%)had no ideal best-corrected visual acuity;31 patients(3.8%)had the fundus disease,31 patients(3.8%)had dry eye and 36 patients(4.4%)had the other reasons.CONCLUSION:LASIK is an alternative surgery.We must perform preoperative assessment carefully,evaluate the test results comprehensively and scientifically,enhance communication between doctors and patients and strictly master surgical indications and contraindications.