Lumps under the skin of the abdomen may be caused by swollen lymph nodes in the abdomen, lipoma, sebaceous cysts and so on. 1. Abdominal lymph node swelling: mostly seen in the abdomen by bacterial or viral infection, the local drainage area may have lymph node swelling, so there will be abdominal subcutaneous lumps. 2. Lipoma: subcutaneous abdominal lumps may be caused by lipoma, which is a kind of common benign tumor that can occur in the trunk, limbs and abdominal cavity and other parts. It is mainly manifested as a subcutaneous swelling with clear boundaries and a soft texture. If the texture is hard, it may also be subcutaneous fibroma. 3. Sebaceous cysts: Due to the blockage of sebaceous gland excretory ducts, there is a gradual increase in sebaceous gland contents, resulting in retention cysts, which will appear as abdominal subcutaneous lumps. Patients with abdominal subcutaneous lumps should go to the hospital in time, complete the examination, clear diagnosis and follow the doctor’s instructions for reasonable treatment.