The invention relates to a black tea fermentation house. The circumferential surfaces of the frame of the house are provided with glass walls, the roof of the house is provided with a cover plate, the cover plate is provided with a plurality of exhaust fans, a heater is arranged on the cover plate, one end of a ventilation tube is connected to the heater, the other end of the ventilation tube is connected to the outlet of an ultrasonic atomizer, the ultrasonic atomizer is connected with a water tube, a plurality of mist discharge tubes are vertically arranged in four corners of the house, every mist discharge tube is provided with ventilation holes, the gas inlet ends of the mist discharge tubes are connected with gas discharge holes at the bottom end of the heater, and a humiture sensor is arranged on the central house frame. The black tea fermentation house mainly solves the problems of low fermentation efficiency, high fermentation cost, complicated and tedious fermentation operating process and large energy consumption of present black tea fermentation apparatuses, and has the advantages of realization of one-shot fermentation of a large amount of black tea, high fermentation efficiency, simple control process, low building cost and high fermentation quality.