s Objective To assess the correlation between the features of optical coherence tomography (OCT) and fundus fluorescein angiography (FFA) in clinically significant diabetic macular edema. Design Prospective case series. Participants 102 patients(177 eyes) with clinically significant diabetic macular edema. Methods Optical coherence tomography and fluorescein angiography typing were done separately in a double-masked manner in each case of clinically significant macular edema. The correlation between FFA types and OCT types were analyzed, and their associations with the best visual acuity, central foveal thickness were evaluated. Main Outcome Measures The FFA features and OCT features of clinically significant diabetic macular edema, central foveal thickness, best visual acuity. Results The prevalence of focal leakage type was higher in the OCT type 1 (70.6%) than in the diffuse leakage type (27.2%) and diffuse cystoid leakage type (2.2%) of fluorescein angiography (P