Disclosed is a composition for textile softener containing a cationic surfactant, the ratio of which C7-C21 alkyl substituents analyzed by HLPC (high pressure liquid chromatography) or GC (gas chromatography) is 0.6 or more, as an effective ingredient, a sheet for textile softener including the same, and method of softening a textile using the sheet. Since the composition for textile softener has excellent dissolving and dispersing effect even in low temperature water, the sheet containing this composition is used at a rinse time during washing procedures to represent excellent anti-static effect and textile softening effect to textiles and clothes.