A method for joining two dissimilar metal plates having different volume resistivity with enhanced joint strength. The method includes overlaying a first metal plate made of first metal and a second metal plate made of second metal with higher volume resistivity and higher melting point in comparison with the first metal, bringing a pair of electrodes into contact with the surface of a portion of the second metal plate overlapping the first metal plate, supplying current between the electrodes so as to resistance-heat the second metal present in a current-flowing region to a temperature lower than the melting point of the second metal and higher than the melting point of the first metal, thereby partially melting the first metal plate with the heat so that an intermetallic compound is generated between the first and second metal plates, and thus joining the first and second metal plates via the intermetallic compound.