A DEPT pulse sequence is well-known 13C-detected, edited-pulse and cross polarization transfer NMR experiment which offers to selective detection capability of CH, CH2 and CH3 groups from each other. The product operator theory is widely used for analytical descriptions of the cross polarization transfer NMR experiments for weakly coupled spin systems. In this study, analytical descriptions of the DEPT NMR experiment have been presented for ISn (I= 1,S= 1;n= 1,2,3,4) spin systems by using product operator theory. Then a theoretical discussion and experimental suggestions were made. It has been investigated that this experiment can be used to edit 14N sub-spectra of partly or full deuterated 14NDn (n=1, 2, 3, 4) groups.