AIM:To observe the clinical efficacy of the oral horse chestnut seed extract for treating macular edema. METHODS: Forty-seven cases (50 eyes) of macular edema patients (fifty eyes) were randomly divided into 2 groups. The conventional therapy (oral vitamin C, E and rutin tablets) was used in control group. The treatment group was treated with oral horse chestnut seed extract and conventional therapy. RESULTS:After 4 weeks observation, the absorption of macular edema in treatment group was better than the control group, the difference was significant (P<0.05), no adverse reactions was observed in treatment group. CONCLUSION: The horse chestnut seed extract is effective for macular edema with no adverse reactions.