By applying the recursion method to the intermetallic mixed compound Mn₄N₁₋xCx with cubic perovskite-type structure we investigate the effects of substitution of C atoms for N atoms on the electronic structure and the magnetic properties of Mn₄N. By calculating the DOS's for the ferrimagnetic states of both Mn₄N and Mn₄N₀.₇₅C₀.₂₅ we have determined the magnetic moments at two types of Mn site, Mn(I)(corner site) and Mn(II) (face center site), which are antiparallel to each other. The obtained magnetic moment of Mn(I) in Mn₄N₀.₇₅C₀.₂₅ is found to be the same with that in Mn₄N while the absolute value of Mn(II) moment increases by the substitution of C atoms. As the result the total ferromagnetic moment decreases by the substitution of C atoms. These results are in good agreement with the observations.Article信州大学理学部紀要 30(1): 25-36(1995)departmental bulletin pape