Feeling a thing next to the belly button may be caused by lipoma, abdominal wall fibroma, sebaceous cysts and other reasons. 1. Lipoma: the lump can be found raised between the skin and muscle, most of the lipoma will not be painful. 2. Abdominal wall fibroma: the tumor is mostly located in the rectus abdominis muscle sheath or in the incision scar, the lump can be palpated when it increases in size, and usually has no obvious symptoms. 3. Sebaceous cysts: If the sebaceous gland secretion next to the navel cannot be discharged normally from the mouth of the gland, resulting in accumulation in the gland, a lump may appear. It is recommended that those who feel a thing next to the navel go to the hospital in time to clarify the cause of the disease and standardize the treatment under the guidance of the doctor, so as not to delay the condition.