We have produced a novel ionic liquid {N,N,N',N'-tetramethylethylene-diaminium-N,N'-disulfonic acid trifluoroacetate ([TMEDSA][TFA]2)}, and identified it by analysis of 1H NMR, 13C NMR, 19F NMR, mass, TG (thermogravimetry) and DSC (differential scanning calorimetry) data. Then, we have applied [TMEDSA][TFA]2 as a dual-functional catalyst for the production of 1,8-dioxo-9,10-diaryl-decahydroacridines by the multi-component reaction of dimedone with arylaldehydes and primary amines. Furthermore, we have proposed a plausible and attractive mechanism based on dual-functionality of the catalyst. Due to dual-functionality of [TMEDSA][TFA]2 (possessing acidic and basic sites), and also possessing two sites of each, it was highly effective and general, and produced the products in high yields.