The invention discloses a coplanar electrode photodiode array and a manufacturing method therefor. A first conductive heavily-doped region and a second conductive doped region are formed on the top side of a low-resistivity substrate and high-resistivity epitaxy type epitaxial wafer, wherein the first conductive heavily-doped region and the second conductive doped region are a negative electrode and a positive electrode of a photodiode respectively. The structure comprises a groove structure formed between the positive electrode and the negative electrode, and the groove structure can be composed of a gap, an insulation material, a conduction structure, a reflective material and an ion implantation unit; and the structure also can comprise the first conductive heavily-doped region, an insulated isolation layer, the conduction structure with an insulation layer or the like formed below the positive electrode and the negative electrode.