Amyloidosis is a disease caused by the deposition of amyloid material in tissues or organs. Homogeneous and structureless amyloid protein is deposited in tissues or organs, resulting in varying degrees of dysfunction in the deposited tissues and organs, which can involve multiple organs throughout the body and can also manifest in the skin. Amyloid is a complex of globulin and mucopolysaccharide that chemically resembles starch, hence the name amyloidosis. The origin of amyloid is less clear and is considered to be a product of antigen-stimulated plasma cells or synthesized by fibroblasts, and is generally classified as primary or secondary. The former are mainly deposited in interstitial tissues and are classified as limited and systemic, while the latter are secondary to chronic inflammatory conditions, such as tuberculosis, rheumatoid, and osteomyelitis. Clinical manifestations, primary cutaneous amyloidosis, mainly mossy amyloidosis, is a rash in men over middle age, and is more pruritic, most often in the front of the shin of the lower leg, contralateral distribution, partly with papule-like fusion, usually have to go to dermatology. Primary systemic lesions, mostly invading the vascular wall, connective tissue, gastrointestinal smooth muscle, causing gastrointestinal bleeding, cardiac and renal failure, skin damage, purpura and hemorrhage of the subcutaneous mucosa. The oral cavity can cause megalingual disease, and the disease can be associated with multiple myeloma. Secondary ones are usually seen in chronic inflammatory lesions, rheumatism, myeloma, tuberculosis, etc. The diagnosis is based on the characteristics of multi-organ involvement, which cannot be explained with known etiology due to the thought of this disease, and the basis for determining this disease is the biopsy, so this disease is mostly seen in skin manifestations, and the second is multi-systemic damage.