The hydrogen storage behaviors of the nitride-based MXenes Ti2N have been investigated by performing density functional calculations. It is observed that H-2-molecules could be adsorbed on and desorbed from Ti2N monolayer with suitable adsorption strength under ambient conditions. Moreover, the stability and hydrogen adsorption behaviors are analyzed by computing adsorption energy, charge population and ab initio molecular dynamic simulations. The Kubas-type interaction of the H-2-molecules with Ti2N monolayer is investigated according to the charge transfer and electronic projected density of states. Specifically, it is found that the maximum hydrogen storage capacity of Ti2N reaches up to 8.555wt%, in which the reversible hydrogen storage capacity is of 3.422wt%. In addition, OH-group-decorated Ti2N has great advantages on hydrogen storage, and the reversible hydrogen storage capacity is of 2.656wt%. Therefore, the 2D Ti2N MXenes are expected for a potential candidate as reversible hydrogen storage materials under ambient conditions.