The stereodynamics of the H+NH reaction and its isotopic variants are investigated by the quasi-classical trajectory method at the collision energies of 8 kcal/mol and 16 kcal/mol based on the ground state potential energy surface of NH2 reported by Zhai and Han Zhai H S, Han K L 2011 J. Chem. Phys. 135 104314. Vector correlations of k- j' and k- k'- j', such as angular distributions of P(θr), P(φr), P(θr, φr) and the distributions of the polarization-dependent differential cross-sections are discussed in detail. The results indicate that for the two collision energies, the isotopic effect on sterodynamic property of H+NH reaction is apparent which could be attributed to the difference in mass factor in isotopy-susbstituting reaction.