The invention discloses a production method of a color fabric imitating cowboy style and relates to the technical field of production of woven fabrics. The production method comprises the techniques of slashing, weaving, dyeing gray fabrics, washing and desizing, finishing and the like. Warp and weft yarn components prepared from different materials are selected for weaving and the dyeing difference of the warp and weft yarn components is utilized, so that the whitening effect of dyed fabrics can be realized; a color separating agent with dye-retarding capability is added into a sizing agent for slashing, and is mixed and sized, so that the color separating agent can be uniformly distributed on the surfaces of warp yarns; when the woven fabrics are dyed by adopting active, indigo blue or reducing dye, the dyeing of dye is stopped by a covering area of the woven fabric, and stripe-shaped color spots with different depths in the direction of warp yarns can be obtained after amylase is adopted at later stage for performing desizing treatment, so that the grey effect of traditional yarn dyed denims is realized. The color imitated denim produced by using the production method has the advantages of vivid style, abundant colors, simple process, high production efficiency, high color fastness and the like.