In this work, poly(ionic liquid)-based porous hybrid materials were facilely prepared through ionic self-assembly method and proposed as adsorbents for removal and separation of ionic dyes. PIL, namely poly-[N,N-dimethyldodecyl-(4-vinylbenzyeammonium chloride], was synthesized by simple radical polymerization and directly assembled with the multi-charged anionic cluster of polyoxometalate (POM) to yield PIL/POM hybrid materials without involving any toxic organic solvents and tedious modification processes. The obtained hybrid materials were characterized by various techniques and utilized as adsorbents for removal of a variety of ionic dyes from water. By adjusting the proportion of PIL and POM in the hybrid materials, the adsorption capability and selectivity towards cationic and anionic dyes could be effectively regulated. The preferred adsorbent showed fast adsorption rate and large adsorption capacity, and was able to selectively remove anionic dyes from cationic/ anionic mixed dyes aqueous solutions. Furthermore, the used adsorbent can be easily collected and regenerated. All the results demonstrate that the PIL/POM hybrid material is an efficient, durable and sustainable adsorbent in water purification treatment.