To figure out the influence of isotope effect on product polarizations of the N(2D)+D2 reactive system and its isotope variants,quasi-classical trajectory(QCT) calculation was performed on Hos potential energy surfacc(PES) of 2A" state.Product polarizations such as product distributions ofP(θr),P(φr) and P(θr,φr),as well as the generalized polarization-dependent differential cross sections(PDDCSs) were discussed and compared in detail among the four product channels of the title reactions.Both the intermolecular and intramolecular isotope effects were proved to be influential on product polarizations.