A high-frequency absorption diode chip comprises a substrate (1); an epitaxial layer (2) is formed on the upper surface of the substrate (1); a base region window (4b) is formed on the epitaxial layer (2); the base region window (4b) comprises a pressure point region (11) and a partial pressure region (12) located at the periphery of the pressure point region (11); the pressure point region (11) is separated from the partial pressure region (12) by means of the epitaxial layer (2); a first ion diffusion layer (6a) is formed in the base region window (4b); an emission region window (7b) is disposed on the first ion diffusion layer (6a); a second ion diffusion layer (8a) is formed in the emission region window (7b); a passivation layer (9) is disposed on each of the upper surfaces of the first ion diffusion layer (6a) and the second ion diffusion layer (8a) in the pressure point region (11); an oxide layer (3) is formed on the upper surface of the first ion diffusion layer (6a) in the partial pressure region (12); and the oxide layer (3) and the passivation layer (9) both extend to the upper surface of the epitaxial layer (2), and the passivation layer (9) separates the oxide layer (3) from the first ion diffusion layer (6a) in the pressure point region (11). The high-frequency absorption diode chip is suitable for peak absorption in an RCD circuit; and the high-temperature current leakage of the chip is lower than that of a traditional diffusion type diode chip by more than 50% at the temperature of 125ºC.