The invention relates to the technical field of gas detection and discloses a high-sensitivity hydrogen sulfide gas detector. The high-sensitivity hydrogen sulfide gas detector comprises a motor, a turbine motor and a toxic gas concentration monitoring box, the turbine motor comprises a shell, a horn-shaped gas inlet port arranged on the upper end face of the shell, an impeller arranged in the shell, and a large-diameter gas conveying port, an opening of the horn-shaped gas inlet port faces upwards, a rotating shaft of the impeller is connected with an output shaft of the motor, the gas conveying port is located at the other end of the rotating shaft and is communicated with the side surface of the shell, the toxic gas concentration monitoring box comprises an internal detection cavity anda hydrogen sulfide gas concentration detection probe arranged in the detection cavity, and one end, far from the turbine motor, of the gas conveying port is communicated with the detection cavity. The high-sensitivity hydrogen sulfide gas detector has the beneficial effects that: the detection sensitivity of the concentration of the hydrogen sulfide gas is greatly improved, the early warning is realized, the malignant accident is avoided, and the sensitivity is high.