PURPOSE: To identify those factors influencing the post-operative satisfaction in myopia patients receiving laser in situ keratomileusis (LASIK) METHODS: This study included 288 consecutive patients who received LASIK between July and December 2001 from two eye clinics located in Seoul and Pusan. Factors that were considered to influence post-operative satisfaction included pre-operative baseline characteristics, pre-operative expectation for treatment outcomes, and treatment outcomes. Before undergoing LASIK, study subjects were asked to rate the degree of their expectation for the improvement of visual functions and symptoms after LASIK on a 5-point Likert-type scale: where 1 referred to 'somewhat worse, ' 2 to 'no change, ' 3 to 'somewhat improved, ' 4 to 'improved, ' and 5 to 'very improved.' Self-administered questionnaire was used to evaluate baseline visual functions and symptoms on a 5-point scale before LASIK. At 6 months after LASIK, the evaluation was repeated to measure treatment outcomes in terms of the difference in the score before and after LASIK. Post-operative satisfaction was also measured at 6 months on a 5-point scale. Multiple regression analysis was performed to examine the independent relationship between influencing factors and postoperative satisfaction. RESULTS: A total of 171 patients (59.4%) participated in the 6-month follow-up investigation. The average expectation scores for the improvement in visual functions and symptoms were 3.8 and 3.4, respectively. The average score for the 7 questions assessing satisfaction was 4.0. The results of the regression analysis showed that the post-operative satisfaction increased with improvement in the visual function (beta=0.16, p< 0.05) and symptoms (beta=0.25, p< 0.05), the degree of preoperative refractive error (beta=0.26-0.67, p< 0.05) and in male patients (beta=0.31, p< 0.1). The pre-operative expectation was not a statistically significant factor in explaining postoperative satisfaction in the regression model. CONCLUSION: The finding from this study was that patients with very severe myopia tended to be more satisfied with the treatment than those with mild myopia, which implies that LASIK can be more beneficial to those suffering from a severe visual condition. Patient satisfaction was also significantly affected by the treatment outcomes experienced after LASIK. This suggests that improving the clinical outcome is the most fundamental requirement for the improvement of patient satisfaction.