Abstract: OBJECTIVE To evaluate the clinical efficacy of Guyang Huashui formula in treating diabetic macular edema (DME) with spleen and kidney yang deficiency type. METHODS A prospective randomized controlled trial was conducted to observe 66 patients (66 eyes) with DME outpatients in the department of ophthalmology in Dongfang Hospital from January in 2016 to December in 2018. Patients admitted to the study should meet the diagnostic criteria for moderate and worse international clinical classification of DME and traditional Chinese medicine (TCM) syndrome type of spleen and kidney yang deficiency. Randomly divided into the experimental group and the control group， 33 cases each， who were given Guyang Huashui formula granules or calcium hydroxybenzenesulfonate capsules and Maizhiling tablets for oral treatment for 3 months. The efficacy was evaluated according to the patient's best corrected visual acuity， macular retinal thickness and volume， and TCM syndrome scores. RESULTS 30 patients in each group completed all treatment and observation. After treatment， the best corrected visual acuity in both groups was significantly improved compared with that before treatment (P<0.05， P<0.01 ) and difference between groups has no significant meaning (P>0.05). The thickness of the retinal film in the macular center of the test group was significantly reduced (P<0.01 ). The thickness of the retinal membrane and the average thickness of the retinal membrane in the macular area of the two groups were significantly reduced (P<0.01)， and the test group was significantly better than the control group (P<0.01). In the trial group， the medical syndrome was clearly improved (P<0.05， P<0.01). The two groups were compared and the difference was significant (P<0.05， P<0.01). CONCLUSION Guyang Huashui formula can significantly improve DME patient's vision and reduced retinal thickness in the macular area so as to relieve their TCM syndrome.