To provide a surface treating method, by which a figure, the pattern of which changes in response to a seeing angle, or the like can be drawn on the surface of aluminum or of its alloy with a simple and low cost means.

By rubbingly scraping the surface of aluminum or its alloy with a brush made of a material having the hardness higher than the hardness of aluminum or its alloy towards a desired direction, a large number of scraping marks parallel to one another are formed so as to draw a desired figure or character pattern by the scraping marks. A complicated figure or the like can be drawn by alternately repeating a masking operation with a different pattern and a rubbingly scraping operation with the brush to different direction by several times.