OBJECTIVE To evaluate changes in corneal thickness after 2, 4, and 6 weeks of frequent-replacement contact lens wearing. METHODS Twenty-eight patients were fitted with ACUVUE (Johnson & Johnson) contact lenses. Central and peripheral corneal thickness was measured before contact lens fitting and after 2, 4, and 6 weeks of wearing. RESULTS Analysis of variance shows that the period of contact lens wearing has no influence on central corneal thickness. After a small increase in the second week, central corneal thickness returns to the initial values in the fourth and sixth weeks of contact lens wearing. Peripheral corneal thickness was statistically related to the time of contact lens wearing (P < 0.01). A statistically significant difference was observed between the baseline and peripheral corneal thickness measurements in the second, fourth, and sixth week of contact lens wearing (P < 0.01). CONCLUSIONS Frequent-replacement contact lenses (ACUVUE) cause a small amount of corneal edema, which is higher in the periphery than in the center. Central corneal swelling disappears after 6 weeks of wearing, but in the periphery it remains stable throughout the period of observation.