Ionic liquids (ILs) have become attractive in membranes for CO2 separation because of the designable structure, high CO2 affinity, and good compatibility and stability. Modification of metal-organic frameworks with ILs is an effective strategy to improve the gas separation performance of mixed matrix membranes (MMMs). In this work, task-specific ionic liquids (TSILs) were incorporated to prepare TSIL@ZIF-67/PIM-1 MMMs and improve CO2 separation performance because of the high CO2 solubility and great compatibility toward ZIF-67 and PIM-1. The TSILs (TMGHIM and TMGHPhO) selectively and reversibly interact with CO2 and improve the interfacial compatibility between ZIF-67 and PIM-1, leading to higher CO2/CH4 and CO2/N-2 selectivities than that of the ZIF-67/PIM-1 MMM and the directly blended membrane (TSIL/ZIF-67/PIM-1). The 10 wt % TMGHIM@ZIF-67/PIM-1 MMM shows enhanced CO2/N-2 and CO2/CH4 selectivities of 13.7 and 10.5, respectively; meanwhile, the CO2 permeability reaches 12,848.5 Barrer and is 2.5 times that of the pure PIM-1 membrane. The TSIL@ZIF-67/PIM-1 MMMs also show good stability against physical aging.