The combination ionic liquids (ILs) with membranes is a potential method for direct NH3 separation. In particular, ILs can modulate the interactions with NH3 and construct pathways in membranes for preferential NH3 transport, which is expected to overcome the trade-off effect and achieve a desirable separation performance. In this work, four metal ILs (MILs) with different metal centres and hydrogen bond donating ability, including [2-Mim][Li(NTf2)2], [Eim][Li(NTf2)2], [Bmim]2[Co(NCS)4], and [Bim]2[Co(NCS)4], were incorporated into sulfonated block copolymers to prepare MIL-based hybrid membranes for NH3 separation. The investigation of structure–performance relationships suggested that the interaction sites and transport channels could be tuned by the MIL type, which greatly affects the NH3 separation performance of the membranes. The Nexar/2-Mim-Li-10 membrane exhibits NH3 permeability of 735.6 Barrer with NH3/N2 selectivity of 844.5 and NH3/H2 selectivity of 154.7, which is higher than other MIL-based hybrid membranes owing to self-assembled transport channels and moderate complexation. Increasing the MIL content and feed pressure significantly improved NH3 separation performance.