The present invention relates to nanoemulsion type synthetic red blood cells having a calcium phosphate coating of controllable thickness, and to a preparation method thereof. According to the present invention, Ca2+ and PO42− coating layers are uniformly and sequentially formed using a layer-by-layer (LBL) coating method while controlling the thicknesses of the coating layers. Thus, the oxygen capacity and oxygen release rate of the synthetic red blood cells can be controlled, and the synthetic red blood cells can be retrieved and reused.
