In this work a method is introduced to calculate the DCX reaction in the framework of Monte‐Carlo Shell Model (MCSM). To facilitate the use of Zero‐temperature formalism of MCSM, the Double‐Isobaric‐Analog State (DIAS) is derived from the ground state by using isospin shifting operator. The validity of this method is tested by comparing the MCSM results to those of the SU(3) symmetry case. Application of this method to DCX on 56Fe and 93Nb is discussed.