Objective To investigate the relationship of magnitude and location between central corneal thickness (CCT) and the thinnest corneal thickness (TCT),and the effect of myopia on corneal thickness.Methods Data obtained with a Pentacam from 300 eyes of 150 patients who had undergone refractive surgery for myopia were randomly divided into 3 groups for a retrospective case control study.The relationship and difference in ocular parameters between the fellow eyes were analyzed by Pearson correlations and paired t tests,respectively.Analysis of variance (ANOVA) was used to compare the data among the multiple groups,and an independent samples t test was used to compare data from the ipsilateral eyes.Results The mean CCT was 555.83±31.83 μm and the mean TCT was 552.88±31.4 μm in the left eyes.The mean CCT was 554.10±31.47 μm and the mean TCT was 549.26±31.25 μm in the right eyes.The TCT location was inferotemporal to the corneal apex in 108/150(72.00％) of the left eyes and in 106/150(70.67％) of the right eyes.There were no significant differences in corneal thickness among the three myopic groups.Conclusion TCT was not consist with the CCT.The TCT location was mainly inferotemporal to the corneal apex in both eyes.Corneal thickness has no significant effect on myopia.