The invention discloses a semiconductor detector for measuring radiation and an imaging device, wherein the semiconductor detector comprises a semiconductor medium capable of absorbing radiation to bemeasured of at least one energy section, an anode electrode arranged on one surface of the semiconductor medium, a cathode electrode arranged on another surface of the semiconductor medium opposite to the first surface, and a signal processing circuit which is connected with the anode electrode and the cathode electrode and processes a detected signal as a numerical value representing energy deposition rate of the radiation, wherein the semiconductor medium receives the incident radiation along the direction parallel with the electrode surfaces, and the anode electrode and the cathode electrode are divided into a plurality of sub-electrode couples at intervals along the incident direction of the radiation for detecting the energy deposition rate of the radiation of corresponding energy sections respectively.