BackgroundAutologous fat injection is getting popular in cosmetic procedures, however, still has a risk of fat embolism. Herein, we report the first case of segmental ischaemic infarction of the iris, which occurred after autologous fat injection into the lower eyelid.Case presentationA 28-year-old Korean woman complained of the discolouration of the iris after the fat injection. Slit-lamp biomicroscopy revealed segmental depigmented atrophic iris with sectoral sphincter palsy.ConclusionsWe found that iris atrophy could be caused by autologous fat transplantation. The plastic surgeons should pay more attention to possibility of fat embolism-induced ocular complications in the procedure of fat injection.