PT. Soman Indonesia is a provider of quality herbal medicine. PT. Soman Indonesia is located on Jalan Labu II, No 20, Medan Petisah, North Sumatra. Through this research, the writer will analyze the brand image that influence the purchasing decisions of Soman herbal medicine. In order to support its operational activities, the company established several product sales points to reach customers directly. The sales point is called “Soman House.” The factor that is suspected to increase the sales is brand image. Brand image is formed from perceived value then provides brand memory that is important to consumers. This research uses the theories about brand image and its influence on customer purchase decision. The framework of this research is to find out the relationship between brand image and customer purchase decision. The methods used by the writer in this research is quantitative descriptive research. Data used in this research are primary data and secondary data. This research uses simple linear regression, hypothesis test and determination coefficient to know the impact of brand image on customer purchase decision. Based on research result, the simple linear regression showed equation of Y = 0.474 + 1.183 X. It means that variable brand image has a straight relationship to customer purchase decision, that if there is an increase on brand image, the customer purchase decision will also increase. The conclusion on this research is the hypothesis test showed that the variable brand image has an impact to customer purchase decision. The determination coefficient has resulted in 72.5% variable customer purchase decision can be explained by variable brand image and the rest of 27.5% can be explained by other factor that is not mentioned in this research. For next researcher, the writer recommend to add other factors that can give impact on customer purchase decision such as price, promotion or trying to use another core business as sample.