The use of ionic liquids (ILs) as demulsifiers of water-in-crude oil emulsions represents a new field of study. The main purpose of this work is to investigate the effect of five ILs, [C(4)mim](+)[NTf2](-), [C(8)mim](+)[NTf2](-), [C(12)mim](+)[NTf2](-), [C(4)py](+)[NTf2](-), and [C(8)mim](+)[ [OTf](-), and a set of operation parameters on the demulsification process, including the heating type (conventional and microwave), IL concentration (0.74-8.9 mu mol/g), effect of alkyl chain length, and effect of cation and anion type on demulsification efficiency. The results indicated that the demulsification was favored when more hydrophobic ILs and longer cation alkyl chains were employed, such as [C(12)mim](+)[NTf2](-), reaching values close to 92% of water removal. Moreover, the joint use of microwaves and hydrophobic ILs allowed us to maximize the demulsification efficiency.