Background: To determined 24-hrs glycemic variations using continuous glucose monitoring (CGM) in cataract surgical patients with normal glucose metabolism receiving dexamethasone therapy.Methods: This was a single-center, randomized, observational and prospective trial. Between June 2017 and December 2018, cataract surgical patients with normal glucose toleration were recruited, and were randomized assigned at a ratio of 1:2 to either receiving 10 mg dexamethasone daily for 3 days after cataract surgical (dexamethasone group) or without dexamethasone therapy (control group). A retrospective CGM was performed at afternoon on -1 day before cataract operation performed for at least 3 days. The primary endpoint was the difference in mean amplitude of glycemic excursions (MAGE) between the two groups.Results: We observed that patients receiving 10 mg dexamethasone daily showing mild increase in mean glucose and hourly mean glucose throughout 24-hrs compared to control group. We also detected that dexamethasone leading to a significant increase in glycemic variation, in term of standard deviation, and a number increase in MAGE and CV%.Conclusion: Our data reveal that short period administration of dexamethasone leading a mild increase in glycemic variations (GV). However, the increased GV may have not clinically relevant. Our data indicates that short duration of 10 mg dexamethasone once daily may be a safe therapy regarding glycemic metabolism in subjects without diabetes.