Considering that attitudes towards biotechnology depend on the type of modifcation used, a study was performed to determine the importance of the type of Genetic Modifcation (GM) in preferences for oil purchased by consumers in Temuco (Araucanía Region, Chile) and the existence of different market segments using a survey of 400 people. A conjoint analysis demonstrated that the type of GM (70.3%) was more important than the price of the oil (29.7%). Four segments were distinguished using an analysis of hierarchical conglomerates, but the type of GM was the most important factor in all segments. Two groups preferred oil without GM and oil with GM that reduces the use of pesticides and rejected oil with GM that increases calcium content; the larger of these groups (42.8%) preferred to pay a lower price, while the other (16.8%) they preferred higher priced oils. One group (27.2%) rejected all types of GM. The smallest group (13.2%) rejected oil without GM and preferred oil with GM that reduces the use of pesticides and oil with GM that increases calcium. All of the groups rejected oil with GM that reduces production costs. The groups were differentiated by the family size, lifestyle, ethnic origin, reading of the labels on foodstuffs, and the variety of oil habitually consumed. The absence of GM in oils is desirable for the majority of consumers (86.8%); however, a high proportion (72.8%) would accept oils with GM that reduces the use of pesticides.