The invention discloses a device and a method for evaluating an occupational health risk of hydropower station staffs, and belongs to the technical field of occupational health risk evaluation of hydropower stations. According to field investigation and data sorting, an on-duty mode and a hazard factor contact situation of the hydropower station staffs are determined. Data acquisition and sortingare carried out on hazard factors contacted by the on-duty staffs in working places; detection data is graded according to evaluation thresholds and grade division of the hazard factors contacted by the on-duty staffs; a distribution ratio of the hazard factors in working areas in different grades is analyzed; a grade distribution situation of the hazard factors contacted in the working places ofa hydropower station is obtained; and whether the occupational health risk of the hydropower station staffs exists or not is judged.