This study aimed to investigate the incidence and clinical characteristics of acute primary angle closure (APAC) during the Coronavirus Disease 2019 (COVID-19) pandemic in China. This was a retrospective study of patients diagnosed with APAC in a glaucoma clinic over a 5-year period. We compared the number of APAC cases during the COVID-19 outbreak (December 7, 2022 to January 7, 2023) with those during the same period in previous years and 2 months prior to the outbreak. We also collected data on the demographic and clinical features of APAC patients, such as age, sex, disease course, visual acuity, intraocular pressure (IOP), and lens opacity. We included 95 eyes of 88 patients with APAC were included. Of these, 65 were female and 23 were male. The mean age was 68.0 ± 8.1 years. The median disease course was 10.8 ± 9.5 days. There was a significant increase in the number of APAC cases during the COVID-19 outbreak compared with the same months over a 5-year period (44 vs 51, P < .001). A higher proportion of women developed APAC during the outbreak period than during the non-outbreak period (P < .001). Eyes with APAC in the outbreak period had a lower mean IOP than those in the preceding 6 months (40.5 ± 8.8 mm Hg vs 46.1 ± 10.1 mm Hg; P = .043). No significant differences were observed in disease duration, lens opacity, or bilateral or unilateral onset between the 2 groups. Our study suggests a potential correlation between APAC and COVID-19, marked by a significant surge in APAC cases concurrent with the COVID-19 outbreak. However, the underlying mechanisms and preventive strategies remain to be elucidated.