Purpose: To study the difference between refractive errors obtained from manifest refraction (MR) and cycloplegic refraction (CR) in first-time spectacle wearers. To study the difference between manifest refractive errors and cycloplegic refractive errors in first-time spectacle wearers. Methods: From January 2002 to December 2002, manifest and cycloplegic refractions were carried out on the patients who visited an ophthalmology clinic for a spectacle prescription for the first-time. The patients were 509 male and 499 female patients aged between from 3 to 15 years old. Results: The cycloplegic refraction showed a less myopia and a more hyperopia compared with the non-cycloplegic refraction. The differences were more in female patients. The CR showed a less myopic and a more hyperopic refractive errors than the MR. The differences were more in female patients. The average results from a pre- and a post-cycloplegic refraction showed a reduction of -0.22D in male, and -0.20D in female for the myopic group. For the myopic group, the myopic refractive errors by MR were -0.22D in male and -0.20D in female higher than the refractive errors by CR. Hyperopic group showed an increase of +0.37D in male, and +0.56D in female. For hyperopic group the hypropic refractive errors by CR were +0.37D in male and +0.56D in female higher than the refractive errors by CR. This difference between the results of a preand a post-cycloplegic refraction was more if the patients were younger. This difference between refractive errors by MR and by CR showed the younger the more and the proportions of pseudo-myopia and or latent hyperopia were also higher with younger patents age. The amounts of with-the-rule astigmatism and the oblique astigmatism were increased for the post-cycloplegic refraction in the CR refraction. Simple astigmatism reduced, but there was no difference found in the amount of astigmatism. The prevalence of simple astigmatism reduced, but there was no difference in the amount of astigmatism. Conclusions: The difference between manifest refraction and cycloplegic refraction was more in younger group. The difference of refrative error between by MR and CR increases with ageing decrease. Pseudo-myopia and latent hyperopia was also found in the younger group. Simple astigmatism reduced after cycloplegic refraction, there was no difference found in the amount of astigmatism. The prevalence of simple astigmatism reduced, but there was no difference in the amount of astigmatism.