A physiotherapy instrument for human body facet joint inflammation is disclosed, relating to the technical field of medical therapy equipment. The physiotherapy instrument includes a rigid therapy cavity and a negative pressure generation control system. The therapy cavity is provided with at least one opening for a limb to enter and leave. The therapy cavity is connected to the negative pressure generation control system by means of an air passage. The therapy cavity is L-shaped, to allow a partial thigh above a knee of a limb and a partial or entire shank below the knee to be put in after bending, and allow a partial arm above an elbow of a limb and a partial or entire forearm below the elbow to be put in after bending. The L-shaped therapy cavity is composed of several parts fitted with each other to form a whole. The opening of the therapy cavity and the limb are fixed by means of a sealed connecting component. A conventional straight cylindrical therapy cavity is changed into the L-shaped therapy cavity, so that upper and lower parts of a joint are put into the therapy cavity at the same time after a knee joint or an elbow joint of the limb bends, thus fundamentally changing the condition of mechanical instability between the straight cylindrical therapy cavity and the limb under a negative pressure. The physiotherapy instrument has a good therapeutic effect, and is lightweight as a whole.
