AIM:To analyse the corneal topography with Pentacam system before LASIK,and to explore the relationship between the corneal topography and the vision improve-ment.METHODS:The Pentacam system was used to analyse the corneal topography shapes before LASIK,and then the uncorrected eye vision,best-corrected vision and astigmatism degree were observed before and 3,6 months after LASIK.RESULTS:Before operation,the rate of symmetrical bow tie and asymmetrical bow tie patterns was 76.13%,the rate of round and ellipse patterns was 19.03%,and the rate of irregular patterns was 4.84%.The different among the three groups had statistical significance(P<0.05).After LASIK,the uncorrected eye vision and astigmatism degree improved with statistical significance after opera-tion(P<0.05).In the three groups,round and ellipse patterns showed the best results,symmetrical bow tie and asymmetrical bow tie patterns ranked the second,and irregular patterns the third.There was significant difference in each shape when compared in the 3rd and the 6th month after operation(P<0.05).CONCLUSION:Using Pentacam system to analyse the corneal topography,we find that there is a relationship between the corneal topography and the vision improvement.