AIM:To investigate the effect of 3% diquafosol sodium eye drops on tear film homeostasis in patients wearing overnight orthokeratology lenses.METHODS:Retrospective study. A total of 340 patients(564 eyes)fitted with night-worn orthokeratology lenses from June to December 2022 were respectively divided into a diquafosol sodium group(200 cases, 323 eyes, treated with 3% diquafosol sodium eye drops)and a sodium hyaluronate group(140 cases, 241 eyes, treated with sodium hyaluronate eye drops). The uncorrected visual acuity(LogMAR), ocular surface disease index(OSDI), non-invasive tear film break-up time(NIBUT), meibomian gland infrared imaging score, and corneal epithelial fluorescein staining were analyzed and compared between the two groups.RESULTS:Compared to baseline, both groups showed significant improvements in uncorrected visual acuity(LogMAR)at 1 wk, 1, and 3 mo after lens wear(all P<0.01). However, no statistically significant difference in uncorrected visual acuity(LogMAR)was observed between the two groups at any time point(all P>0.05). No significant differences in NIBUT or OSDI scores were found between the groups before and at 1 wk after lens wear(all P>0.05). At the 1- and 3 mo follow-ups, the 3% diquafosol sodium group demonstrated significantly longer NIBUT(all P<0.001)and lower OSDI scores(all P<0.001)compared to the sodium hyaluronate group. After wearing lens for 3 mo, the meibomian gland infrared imaging scores were significantly better in the diquafosol sodium group(P<0.001), whereas no significant intergroup difference was observed in corneal fluorescein staining(P>0.05). Furthermore, the incidence of adverse events during the study period did not differ significantly between the two groups(P>0.05).CONCLUSION:Compared with sodium hyaluronate, 3% diquafosol sodium eye drops were more effective in maintaining tear film homeostasis in patients wearing overnight orthokeratology lenses.