Asphaltenes precipitation and deposition is one of the main problems in the petroleum industries which has attracted the attention of many scholars. Precipitation and deposition of asphaltenes can lead to many problems in oil reservoirs such as plugging the pores of the reservoir rocks and changing the wettability of the rocks from water wet to oil-wet. This ultimately causes a reduction or puts an end to production from reservoirs. Therefore, understanding the factors affecting the formation of asphaltenes precipitation can help us to avoid these drawbacks. Several factors including pressure, temperature, and composition changes have been studied in the literature. The effects of these parameters on the stability of asphaltenes are almost clear. However, the effects of water emulsions, which are formed during the water-based enhanced oil recovery (EOR) methods such as smart water and low salinity water flooding, on the instability of asphaltenes are still unknown and blurred. In this study, the effects of several synthetic brines which were prepared by different salts in a wide range of concentrations were investigated to understand the mechanism of ions on the instability of asphaltenes. It was found that the divalent cations have more effects on the instability of asphaltenes compared to monovalent cations due to the chelate formation. Furthermore, the presence of divalent anions in the system can hinder the effect of cations on the instability of asphaltenes.