The invention discloses a multifunctional woollen sweater finishing agent containing marine mud. The multifunctional woollen sweater finishing agent is prepared from the following raw materials in percentage by weight: 6-20% of a marine mud solution, 0.5-3% of a cinnamomum camphora leaf extract, 0.3-1.5% of a Xingan rhizoma cimicifugae root extract, 1.5-3% of a banyan gum liquid, 0.01-1.2% of tea saponin, 5-15% of a softening agent, 5-10% of propylene glycol block polyether, 1.5-3% of dodecyl dimethyl betaine and the balance of deionized water. Therefore, a woollen sweater treated by using the multifunctional woollen sweater finishing agent has the effects of preventing bacterium and eliminating odor, preventing ultraviolet light, killing mints and insects, preventing static electricity and emitting fragrance, meanwhile is capable of releasing nutrient healthcare components and promoting human body health, has a remarkable property of wrinkle and shrinkage prevention, and is long in service life and relatively good in effect, and the wollen sweater can be excellent in brightness, softness, smoothness, slipperiness, fullness, brightening and the like, and the system can be kept stable for a long time. An advantageous direction is provided for recycling use of marine mud, and relatively great predicable economic and social benefits can be made.