The concept of porous liquids (PLs) was initially proposed and divided into three types in 2007 by James, which combine the merits of porous solids and flowing liquids. Recently, PLs have made great progress in preparations and applications. However, challenges for PLs still present to be addressed including their high density, viscosity melting temperatures, and materials cost, which severely limit their large-scale applications in flowing systems. Therefore, it is urgent to look for ideal sterically hindered solutions to construct PLs materials. Notably, the unique properties of ionic liquids (ILs), such as the tunable physicochemical properties for task-specific applications, economic, low regeneration energy requirements, enable them as promising candidates for constructing novel porous ionic liquids (PILs). Over the past five years, PILs based on ILs and existing advanced porous solids, such as porous organic cages (POCs), metal-organic frameworks (MOFs), porous carbons, zeolites, porous polymers, etc., have successively witnessed the achievement in synthesis strategies and applications. Notably, PILs exhibit remarkable properties including permanent porosity, negligible volatility, high thermal/chemical stability, non-corrosivity, adjustable melting temperature, viscosity, high gas solubilities, and fast gas diffusion, which have accelerated their applications in gas adsorption/separation, chiral separation, catalytic conversion, extraction, molecular separations, and other fields. In this review, we summarized recent research progress on the synthesis strategies, properties, and applications of PILs. In the end, challenges and future developments for PILs are summarized and prospected.