Ocular manifestations have been well recognized in coronavirus disease 2019 (COVID‐19) outbreak. Several studies have detected ocular manifestations in patients after COVID‐19. However, little is known about the retinal and vitreal alterations in patients before and after COVID‐19 infection. This study aimed to investigate the retinal and vitreal alterations in patients before and after contracting COVID‐19 infection using swept‐source optical coherence tomography (SS‐OCT) and angiography (SS‐OCTA). A total of 38 participants (76 eyes) were enrolled and followed‐up 1 month after COVID‐19 infection. Then, 26 patients (52 eyes) were evaluated 3 months after COVID‐19 infection. Compared with the pre‐COVID‐19 status, patients with 1‐ and 3‐month post‐COVID‐19 statuses had significant thinning of ganglion cell and inner plexiform layer, thickening of inner nuclear layer, a decrease in the vessel density (VD) of superficial vascular complex, and an increase in the VD of deep vascular complex. Meanwhile, alteration in parameters of foveal avascular zone (all p < 0.05) and hyper‐reflective dots in the vitreous of 27 patients (54 eyes) (71.1% vs. pre‐COVID‐19, 34.2%, p = 0.006) were observed. These findings suggest significantly retinal and vitreal alterations occurred in patients after COVID‐19 infection, possibly due to direct or indirect virus‐induced injuries. Further longitudinal studies are required to investigate the long‐term effects of COVID‐19 infection on the human eyes.