There is a round hard thing under the left rib cage may be sebaceous cysts, fibroids, lipomas, etc., the specifics need to be judged by a doctor, not subjective. 1. Sebaceous cysts: may be due to the skin is not clean so that the sebaceous gland blockage caused by the accumulation of waste, and can not be discharged normally, thus appearing under the left rib cage there is a round hard things. 2. Fibroma: its etiology is not clear, usually patients in the occurrence of local trauma, tissue recovery process, may be formed on the skin surface round hard things. 3. Lipoma: usually due to excessive alcohol consumption, often eat animal offal and other factors to make fat tissue deposition, there may be a round hard thing under the left rib cage. There may be other factors under the left rib cage, the specific circumstances need to go to the hospital for further consultation, to clarify the cause of the disease, to give targeted treatment.