The kinetic analyses and computer simulations were carried out on the pattern formation in phase transitions of the alloys, in which three different types of order parameters are involved; the one is the composition, and the other two sare the B2 and DO3types of order. Three different cases were investigated; one is an isotropic phase transition from A2 to A2+DO3, observed in Fe3Al, another is an anisotropic transition from B2 to B2+DO3, observed in Fe‐Si, and the third is a simple ordering from B2 to DO3, also observed in Fe‐Si, and the third is a simple ordering from B2 to DO3, also observed in Fe3Al. The results of our kinetic investigation turned out consistent with the observations.