Indocyanine green angiograms of the macular region in 40 human eyes were evaluated in order to demonstrate the characteristics of the circulatory patterns of the submacular choroid. During both the early and the late phases of choroidal fluorescence nonuniform fluorescence was found. This implies the existence of watershed zones between choroidal arteries and between choroidal veins. A horizontal line running through the fovea was found to form a boundary between arterial systems, and also, in the majority of cases, between venous system.