To investigate the effect of overnight orthokeratology (OOK) on ocular surface and blinking patterns in children and adolescents.A prospective cohort study was conducted including 27 eyes of 27 children from Beijing Tongren Hospital who received OOK correction and 31 eyes of 31 spectacle wearing children. Tests were performed before and at 3 and 6 months after OOK wear. Ocular surface assessment included tear meniscus height, noninvasive tear breakup time, lipid layer thickness, number of incomplete blinks, number of total blinks, and fluorescein tear breakup time.Before treatment, there were no statistically significant differences in various indicators between the two groups. After wearing OOK for 3 months and 6 months, there were no significant differences between the tear meniscus height, noninvasive tear breakup time, lipid layer thickness, number of incomplete and total blinks, fluorescein tear breakup time groups, and upper and lower lid meibomian gland atrophy rate (P>0.05). However, the corneal fluorescein staining scores in the OOK group were significantly higher than those in the spectacle group (P<0.001).Short-term use of OOK in children and adolescents has a relatively minor impact on ocular surfaces and is considered relatively safe to use. However, it significantly increases corneal fluorescein staining scores, which may suggest the presence of corneal epithelial damage.Copyright © 2025 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the Contact Lens Association of Opthalmologists.