Through collocating colorized yarns and patterning weaving, a variety patterns of tufting carpet are realized. Patterning system is the core in tufting carpet machine; its performance determines the whole machine’s performance and weaving quality. In this paper, the patterning principle of single electronic-roller such as electromagnetic clutch type, servo motor type and step motor type, and the mulriple patterning principle such as two types or more than two types Electronic-Roller, was researched, the corresponding patterning mechanisms was designed, the approach realizing various patterning ways in mulriple patterning was exposited. The patterning principle exposited in this paper solves the general problem in designing patterning mechanism. The patterning systems developped on this principle have been applied in a variety of tufting carpet machines, and a variety of high precision carpet products have been woven.