Purpose: Indocyanine green (ICG) is an albumin and lipoprotein binding dye absorbing in the far red used in angiography to visualize choroidal vessels (ICGA). To guide interpretation, ICG transport in the choroid, retinal pigment epithelial (RPE) and retina of rats was studied. Methods: Two conditions were used: RPE/choroid organoculture (OC), incubated for 45 min in DMEM medium, 1% FBS containing 0.25 mg/ml ICG and RPE/choroid and neural retina flat-mounts at 1 and 6 hours after intravenous ICG injection (IV). Early and late sequences of ICGA were recorded until 6 hours. Ultra-deep red confocal microscope was used to localize ICG in flat-mounts and immunohistochemistry was performed for caveolin-1 (CAV1), tryptase (mast cell marker) and tubulin β3 (TUBB3)(nerve marker). Results: In the OC, ICG penetrated homogeneously in the cytoplasm and stained the membranes of the RPE. At 1h after IV injection, ICG appeared in fine granules in RPE, partly labeled with CAV1 and decreasing at 6h. At 1h and 6h, ICG was found in the retinal vessels, faintly in the inner retina and in photoreceptor outer segments at 6 hrs. In the choroid, ICG co-localized with mast cells, immunostained with tryptase and accumulated along the large TUBB3-labeled nerve bundles. Hypothesis was raised on the interpretation of late ICGA infrared photography in case of transthyretin amyloidosis with neuropathy. Conclusions: Beside being a vascular dye, ICG is transported from the vessels to the RPE towards the outer retina. It stains mast cells and large choroidal nerves. These observations could help the analysis of ICG-A images.