The invention discloses a diamond ultraviolet detector three-dimensional electrode structure, which comprises a monocrystal diamond substrate and an intrinsic monocrystal diamond epitaxial layer, which are laminated. The surface of the diamond epitaxial layer is provided with a plurality of parallel diamond bars in an outward protruding manner. The surface of the diamond epitaxial layer is also provided with two metal electrodes pad, which serve as a positive electrode and a negative electrode respectively. Even numbers of interdigital electrodes pass through the diamond bars vertically at equidistant intervals. The interdigital electrodes 5 are numbered as 1,2,3,..., n according to the arrangement sequence of the interdigital electrodes, wherein the interdigital electrodes, the number ofwhich is odd, are connected to the same metal electrode pad 4, and the interdigital electrodes, the number of which is even, are connected to the other metal electrode pad 4. The diamond ultraviolet detector three-dimensional electrode structure solves the problems of difficult separation of a substrate and a film, long collection time of current carriers and low collection efficiency of a vertical sandwich electrode structure, and meanwhile, solves the problem of poor electric field uniformity when a coplane interdigital electrode structure is adopted, thereby improving response and time response performance of the detector.