The invention relates to a fabric conditioning composition, and provides a hyperconcentration anti-yellowing softening composition. The composition is composed of, by weight, 40-70 parts of treeing positive ion softening agents, 60-90 parts of a modified siloxane mixture, 10-30 parts of films, 5-10 parts of a solubilizer and 3-7 parts of anti-yellowing components, wherein the modified siloxane mixture is composed of modified siloxane A and modified siloxane B. The product is different from a traditional softening agent, has a hyperconcentration feature, can be added with water according to a proportion to be a softening agent, and is used for any large washing machine, and the corresponding usage quantity of the product for every 100 kilograms of dry linen is only 0.3-0.5 kilogram, and isquite low. Hotel towel type linen treated with the softening agent has the advantages of being good in softening effect, high in pure whiteness, good in hydrophilicity, resistant to static electricityand free of yellowing after being rapidly dried at the temperature of 130 DEG C.