The objectives of this study are 1) to study customer behaviour and essential factors that influence customer choice of a petrol station; 2) to determine marketing strategy to increase sales of Patarakit Petroleum, a petrol station located in Na Chueak District, MahaSarakham province at 20 per cent in 2014 by randomly observing and studying behaviour of 400 petro station’s customers. The study indicated significantly numerous factors that vitally influence on customers’ selection of the petro station, where they purchase oil products and related services, including; petro price, location, and customer services. By considering throughout the principle of General Environment Competitive, SWOT Analysis and marketing position, Patarakit Petroleum should implement these three (3) following projects; Project 1 Employee Development, Project 2 Clean and hygienic facilities, Project 3 Coupons Promotions,by 270000 baht in order to increase sales within 2016.