This study focuses on the potential impact of a chemical enhanced oil recovery (EOR) operation on the separation of diluted heavy oil emulsions. The main objective was to underline through experiments on a real crude oil the problems related to the formation of stable emulsions which may be difficult to break. We studied first the influence of alkaline, surfactant and polymer on the formation and separation of emulsions formed under gentle conditions of agitation. In a second step, we analyzed the impact of alkaline and surfactant on emulsification under strong shearing conditions as well as their impact on the efficiency of separation of water-in-crude oil emulsions by the main processes used on the production field, i.e., chemical demulsification and electrocoalescence.