The vague pain under the right posterior rib cage can be caused by several reasons: first, herpes zoster: the early stage of herpes zoster can have vague pain under the rib cage, and after the incubation period, a visible herpes can appear. In the early stage, it can be observed, and after the appearance of herpes, it should be diagnosed and treated at the dermatology department. Second, intercostal neuralgia: intercostal neuralgia can appear as pain in the intercostal nerve below the rib cage, often as hidden pain or radiating pain, which should be diagnosed and treated according to physical examination. Third, rib disease: tumors of the ribs can lead to hidden pain in the early stage of the disease, while pathological fractures can have obvious pain, and CT and X-ray of the ribs should be taken for diagnosis. Fourth, dermatomal neuritis: if there is dermatomal neuritis, it can also lead to hidden pain and tingling of the dermatomal nerve below the ribs, which needs to be diagnosed based on physical examination.