The invention belongs to the technical field of medical equipment, and particularly relates to a medical ultrasonic examination breast fixing device. The medical ultrasonic examination breast fixing device comprises a detection bed, a top plate is arranged at the top end of the detection bed in parallel, the top plate is of a concave structure, a groove is formed in the top plate, a bidirectionalscrew is rotatably connected into the groove, one end of the bidirectional screw is connected with a motor, the bottom end of a sliding block is rotatably connected with a bracket through a rotating shaft, and the bottom end of the sliding block is connected with the bracket; the bracket is of a C-shaped structure, and the bottom end of the bracket is of a U-shaped structure; a first stand column,a first supporting column, a cavity, a second stand column, a threaded shaft, a rotating disk, and an umbrella-shaped gear are installed on the two sides of the detection bed, the height of a breastcover shell can be conveniently adjusted, and adjusting can be conveniently carried out according to patients of different sizes; the bracket, a rack, a cylinder and the breast cover shell are installed at the bottom of the top plate, the fixation of breasts is facilitated, and meanwhile, covering of the breasts can prevent the patients from being shy.