In oil fields, separators are used to separate oil and gas contained in the crude oil pumped from the wells before processing. Although there are many factors influencing the performance of these separators, one of the crucial problems is the formation of foam due to the impurities present in the crude. Another operating problem is carry-over, which occurs when free liquid escapes with the gas phase. Of the several methods used to control foam, chemical control by use of antifoam agents is very important. In this work, the main objective is to study the poor separation of oil and gas due to foaming and the carry-over problem in separators observed in one of the oil fields in Kuwait. Studies were also conducted on the effect of a silicone antifoam agent used to control foaming in order to increase the separation efficiency and thereby increase the production capacity.