Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most prevalent human enzyme deficiency, affecting an estimated 400 million people worldwide. G6PD deficiency increases erythrocyte vulnerability to oxidative stress and may precipitate episodes of hemolysis when individuals are exposed to triggering agents. Although central retinal vein occlusion (CRVO) does occur in G6PD-deficient individuals, G6PD-deficient individuals exposed to oxidative stressors have not been previously reported to have an increase in CRVO incidence. This is a case of an Army Ranger who deployed to Afghanistan with unrecognized G6PD deficiency and was placed on primaquine following his return to the United States and subsequently developed CRVO. Primaquine is a well-recognized cause ofhemolysis in individuals with G6PD deficiency. Hemolytic anemia may contribute to thrombosis as a result of increased erythrocyte aggregation and erythrocyte-endothelium interaction. This case underscores the continued need for routine G6PD screening and avoidance of known triggers in G6PD-deficient individuals.