Only triangle, square and regular hexagon can form regular tessellation. In fact the basic shape of regular tessellation can be decomposed to triangle, in manners of rotation or dislocation the triangle will get the bone cells of regular tessellation, and the regular tessellation can be completed by the repeat of the bone cells. On the basis of constitution in regular tessellation, the regular tessellation can be classified into triangle fit, fabric triangle fit and casual form fit, among which the triangle can be further divided into repeat rotation fit, dislocation half-body fit and inversion symmetry fit.