PURPOSE: To express denim-like pattern by pretreating a textile material with a cationizing agent, drying the textile material, applying an oxidizing agent thereto so as to express pattern effects, drying the textile material and dyeing the textile material with a reactive dye, a direct dye, etc., in the absence of an alkali or a reducing agent.

CONSTITUTION: A textile material comprising cotton is pretreated with a sizing agent such as PVA and dried to afford warp and the warp and the cotton weft are woven and the resultant woven fabric is pretreated with a cationizing agent which is a quaternized or non-quaternized reaction product of polyethylene imines of formula I [X is a residue of the formula (CH2CH2-NH)c; (a) and (b) are each 0-600 and a+b is 60-600; c is 0-50] with an alkylating agent, preferably represented by formula II [A is a radical of alkylating agent; Z is direct bond or divalent bridge element], and an oxidizing agent (e.g. persulfuric acid) is applied to the fabric so as to form pattern and dried and dyed or printed with a reactive dye, a direct dye, a water-soluble sulfur dye, a pigment dye, etc., to provide a woven fabric to which denim pattern is expressed.