Disclosed water-washable silk composite fiber is characterized by being prepared from the following raw materials in parts by weight: 18-22 parts of silk, 11-13 parts of wool, 4-7 parts of cuprammonium rayon, 6-8 parts of polyester fiber, 8-10 parts of newdal fiber, 10-12 parts of bast fiber, 0.6-1.1 parts of nanometer TiO2, 6-9 parts of aloe viscose fiber, 0.7-0.9 parts of hydroxypropyl methyl cellulose, 0.8-1.4 parts of polypropylenglycol diglycidyl ether, 100-110 parts of 1-butyl-3-methylimidazolium dibutyl phosphate, 110-120 parts of 1-ethyl-3-methylimidazolium diethylphosphate, 1-3 parts of radix aucklandiae, 2-4 parts of cortex moutan, 3-5 parts of an auxiliary agent, and proper amount of water. By adding cuprammonium rayon and nanometer TiO2, the silk composite fiber has performances of resisting ultraviolet, resisting static electricity, resisting water washing and the like; and additionally by adding aloe viscose fiber, the Chinese herbal medicines and other compositions, the prepared silk composite fiber has the characteristics of resisting bacteria, diminishing inflammation, light and soft texture, excellent air permeability, high strength and high elasticity, and thus the silk composite fiber is repeatedly cleanable and keeps comfortableness, and is not flat or sunk after being used for a long time.